Rapid Exchange Catheter with Stent Deployment, Therapeutic Infusion, and Lesion Sampling Features

ABSTRACT

A catheter is insertable into a vessel within a mammalian body. The catheter includes a tubular body, at least one channel extending along the tubular body; and a central lumen. The tubular body includes an exterior surface, a first end and a second end, and defines a length between the first end and the second end. The channel passes between a first opening and a second opening and includes a slot in the tubular body between the channel and the exterior surface of the tubular body such that a tubular member can be passed between the channel and the exterior surface. The slot extends from the first opening to the second opening and includes a pair of edges. The central lumen extends along the tubular body at least for a portion of the length of the tubular body. The catheter can be used as a rapid exchange catheter, for stent deployment, for drug delivery or therapeutic infusion with or without electroporation, to provide localized heat, to provide ultrasonic visualization and ablation, and to examine for vulnerable plaque. The catheter may have multiple balloons.

RELATED APPLICATIONS

This application claims priority from U.S. Provisional PatentApplication No. 60/331,125, filed on Nov. 8, 2001, and titled MarkerCatheter with Optional Rapid Exchange Capabilities, and U.S. ProvisionalPatent Application No. 60/347,291, filed on Jan. 14, 2002 and titledSlot for Directing a Wire along a Portion of a Tubular Vessel.

TECHNICAL FIELD

This invention relates to a rapid exchange catheter with multipleutilities for use inside mammalian tubular vessels or structures, andmore particularly allows the catheter to be removed from around a guidewire by using a slot or channel to hold the guide wire.

BACKGROUND

During catheter-based procedures, the physician often visualizes thearea being treated under fluoroscopy and visualizes the catheter and/ortreatment area using radiopaque materials. One method of visualizing isto fabricate the catheter from a polymer that has been compounded withany of the radiopaque materials that are known in the art, such asbarium sulfate, bismuth trioxide, bismuth subcarbonate, tantalum and/orother known combination of radiopaque additives. Another known method isto put one or more marker bands around the outer diameter of thecatheter at various positions at the distal end of the catheter. Themarker bands can be spaced at known distances along the length of thecatheter such that a fluoroscopic procedure can be used to determinedistances of, for example, a lesion. Contrast dyes also are used tovisualize the treated area by injecting a contrast dye through thecatheter while the fluoroscope is being operated. The physician then cansee the vessel in which the catheter is positioned, as well as anylesion past which the contrast dye flows.

In the procedure, the physician may use a guiding device, such as aguide wire, to controllably reach the lesion or area to be treated. Oncethe guide wire is in position, the physician may need to pass one ormore catheters, tubular devices, and/or medical devices along the guidewire to the lesion or treatment area. The physician may pull thecatheter or tubular device back along the guide wire and finally off ofthe guide wire. A difficulty of this, however, is that the guide wiremust be very long (i.e., longer than the catheter) in order to pull thecatheter off the guide wire without needing to first or also pull theguide wire out of the patient. A known solution to this problem is theuse of a rapid exchange configuration in which the distal end of thecatheter has a pair of opening into a lumen and through which the guidewire may be passed by inserting the proximal end of the guide wirethrough the distal most opening and then passing the proximal end of theguide wire out of the proximal opening of the lumen. For example, such aconfiguration is described by Yock (U.S. Pat. No. 5,451,233), which isincorporated by reference herein in its entirety.

One common application of rapid exchange and marker catheters is duringcoronary angioplasty, which refers to the use of an inflatable balloonto increase the blood flow through a stenosis (i.e., a partially blockedsection of a blood vessel feeding the heart). A typical coronaryangioplasty consists of three steps. First, a physician inserts aguiding catheter into a patient's blood vessel, typically through thefemoral artery at the top of the patient's leg. The guiding catheter isadvanced toward the heart through the patient's blood vessel, stoppingshort of the coronary arteries, and is then fixed in place. Next, thephysician inserts a guide wire into the guiding catheter until thedistal end of the guide wire exits the guiding catheter and enters thecoronary artery. The physician then positions the guide wire across thestenosis to be treated in the coronary artery, and the guide wire isfixed in place. Finally, the physician advances a balloon catheter alongthe guide wire until the balloon exits the guiding catheter and ispositioned across the stenosis. The physician then inflates the balloonto treat the stenosis, deflates the balloon, and removes the ballooncatheter without disturbing the placement of either the guide wire orthe guiding catheter.

Physicians frequently need to exchange balloon catheters during a singlecoronary angioplasty procedure. For example, if a stenosis blocks mostof the blood flow through a vessel, the physician may first need to usea small balloon to increase the size of the opening through thestenosis, and then use a larger balloon to further increase the opening.Another example of a catheter exchange is when a physician uses a firstballoon catheter to open a lumen and a second catheter to deploy astent.

SUMMARY

In one general aspect, a catheter is configured to be inserted into avessel within a mammalian body. The catheter includes a tubular body, atleast one channel extending along the tubular body; and a central lumen.The tubular body includes an exterior surface, a first end and a secondend, and defines a length between the first end and the second end. Thechannel passes between a first opening and a second opening and includesa slot in the tubular body between the channel and the exterior surfaceof the tubular body such that a tubular member can be passed between thechannel and the exterior surface. The slot extends from the firstopening to the second opening and includes a pair of edges. The centrallumen extends along the tubular body at least for a portion of thelength of the tubular body.

Embodiments of the catheter may include one or more of the followingfeatures. For example, the catheter may further include a balloonextending around the tubular body proximal of the second end of thetubular body, at least a portion of the balloon being in contact withthe exterior surface of the tubular body. The balloon may extend intothe channel for at least a portion of the length of the channel. Theballoon may further include a first surface extending from the channeland a second surface extending from the channel. Each of the firstsurface and the second surface may include a radially extending channelpassing between the channel in the tubular body and an opening on anouter surface of the balloon. The catheter may further include a bandencircling at least a portion of a circumference of the tubular bodyunder the balloon.

The edges of the slot may overlap, be aligned and in contact along atleast a portion of the length of the edges without being connected, orbe aligned and spaced apart from one another.

The balloon may include at least two discrete diameters. The balloon mayinclude a diameter that is tapered along a length of the balloon.

The catheter may further include a band encircling at least a portion ofa circumference of the tubular body proximal of the second end of thetubular body. The channel may pass below the band.

In another general aspect, a catheter is configured to be inserted intoa vessel within a mammalian body. The catheter includes a tubular bodyand at least one tube. The tubular body includes an exterior surface, afirst end and a second end that define a length between the first endand the second end, and a central lumen extending along the tubular bodyat least for a portion of the length of the tubular body. The tube hasan exterior surface and extends along the exterior surface of thetubular body at least for a portion of the length of the tubular body.The tube includes a first opening, a second opening, and a passage waypassing between the first opening and the second opening.

Embodiments of the catheter may include one or more of the followingfeatures. For example, the catheter may further include a balloonextending around the tube and the tubular body proximal of the secondend of the tubular body, at least a portion of the balloon being incontact with the exterior surface of the tubular body and the exteriorsurface of the t tube. The tube may include a channel that includes aslot opening into the passage way such that a tubular member can bepassed between the channel and the exterior surface of the tube. Theslot extends from the first opening to the second opening and includes apair of edges.

The catheter may further include a band encircling at least a portion ofa circumference of the tube proximal of the second opening of the tube.

The balloon may extend into the channel for at least a portion of thelength of the channel. The balloon may further include a first surfaceextending from the channel and a second surface extending from thechannel. Each of the first surface and the second surface may include aradially extending channel passing between the channel in the tube andan opening on an outer surface of the balloon. The catheter may furtherinclude a band encircling at least a portion of a circumference of thetube under the balloon.

The edges of the slot may overlap, be aligned and in contact along atleast a portion of the length of the edges without being connected, orbe aligned and spaced apart from one another.

The balloon may include at least two discrete diameters. The balloon mayinclude a diameter that is tapered along a length of the balloon.

In another general aspect, a catheter is configured to be inserted intoa vessel within a mammalian body and track a guide wire. The catheterincludes a tubular body and at least one coiled member extending fromthe tubular body. The tubular body has an exterior surface, a first endand a second end, a length defined between the first end and the secondend, and a central lumen extending along the tubular body at least for aportion of the length of the tubular body. The coiled member extendsfrom the second end of the tubular body and includes one or moreextension members and one or more loop members configured to receive aguide wire and defining an inner diameter of each loop. The loop membersare connected to the extension members and define a first opening and asecond opening.

Embodiments of the catheter may include one or more of the followingfeatures. For example, the catheter may further include a balloonextending around the tubular body proximal of the second end of thetubular body and being in contact with the exterior surface of thetubular body. The loop member may have a closed circumference. Theclosed circumference may be openable. The loop member may have an opencircumference.

In another general aspect, a guide wire can be removed from a catheter.The method of removing a guide wire from a catheter includes providing acatheter that includes a tubular body, at least one channel extendingalong the tubular body, and a central lumen. The tubular body includesan exterior surface, a first end and a second end, and defines a lengthbetween the first end and the second end. The channel extends along thetubular body at least for a portion of the length of the tubular body.The channel passes between a first opening and a second opening and hasa slot in the tubular body between the channel and the exterior surfaceof the tubular body. The slot extends from the first opening to thesecond opening and includes a pair of edges. The central lumen extendsalong the tubular body at least for a portion of the length of thetubular body. The method also includes inserting a guide wire into thechannel, advancing the catheter along the guide wire, and removing theguide wire from the channel. Removing the guide wire includes passingthe guide wire from the channel to the exterior surface of the tubularbody through the slot in the tubular body. Embodiments of the method mayinclude one or more of the features described above.

In another general aspect, a guide wire can be removed from a catheter.The method of removing a guide wire from a catheter includes providing acatheter that includes a tubular body and a tube. The tubular bodyincludes an exterior surface, a first end and a second end, a lengthdefined between the first end and the second end, and a central lumenextending along the tubular body at least for a portion of the length ofthe tubular body. The tube includes an exterior surface and extendsalong the exterior surface of tubular body at least for a portion of thelength of the tubular body. The tube includes a first opening, a secondopening, and a passage way passing between the first opening and thesecond opening. The method also includes inserting a guide wire intopassage way in the tube through either of the first opening and thesecond opening in the tube, advancing the catheter along the guide wirethrough the tube; and removing the guide wire from the passage way.Removing the guide wire includes withdrawing the guide wire from thepassage way through either of the first opening and the second openingin the tube. Embodiments of the method may include one or more of thefeatures described above.

In another general aspect, a guide wire can be removed from a catheter.The method of removing a guide wire from a catheter includes providing acatheter that includes a tubular body and at least one coiled member.The a tubular body includes an exterior surface, a first end and asecond end, a length defined between the first end and the second end,and a central lumen extending along the tubular body at least for aportion of the length of the tubular body. The coiled member extendsfrom the second end of the tubular body and includes one or moreextension members and one or more loop members configured to receive aguide wire and define an inner diameter of each loop. The loop membersare connected to the extension members and define a first opening and asecond opening. The method also includes inserting a guide wire into theloop member through either of the first opening or the second opening,advancing the catheter along the guide wire through the loop member, andremoving the guide wire from the loop member. Removing the guide wireincludes withdrawing the guide wire from the loop member through eitherof the first opening or the second opening. Embodiments of the methodmay include one or more of the features described above.

The catheters, marker attachment, band, and/or coil devices andtechniques described herein can advantageously enable the physician tomore accurately determine the length and diameter of a lesion. In thismanner, the physician can properly size a subsequent step, secondaryoperation, or therapy, such as the placement and inflation of a balloonand/or stent to open and maintain the patency of a vessel. Thecatheters, marker attachment, band, and/or coil devices and techniquescan advantageously facilitate rapid exchange over a guide wire, reduceor eliminate the need for a long guide wire, provide improvedvisualization of the device and/or lesion, and provide accuratemeasurement of, for example, the length and diameter of a lesion, suchas in a coronary artery. In particular, they allow a physician to removea catheter from around a guide wire. The catheters, marker attachment,band, and/or coil devices and techniques can advantageously provideaccurate sizing of a secondary therapeutic device, such as a stent orballoon, to the lesion, is easy to use, provides rapid exchange betweenguide and diagnostic catheters, between diagnostic and therapeuticcatheters or device, and between therapeutic devices of different sizes.The marker attachment, band, and/or coil devices and techniques canadvantageously be fabricated as a separate stand-alone device that canbe attached to commercially available catheters and devices at the timeof use or during manufacture of the catheter. Thus, the physician candecide at the time of a procedure to take a measurement and mount amarker attachment, band, or coil to, for example, an inexpensiveoff-the-shelf diagnostic, guide, infusion, or angioplasty catheter ordevice and take the measurement.

The rapid exchange catheter designs herein advantageously do not requirean internal guide wire lumen, can allow complete removal of a catheterfrom around the side of a guide wire, can provide vessel access throughan inflated balloon for several purposes including lesion sample accessand retrieval, and can provide non-complete circumferential inflatedballoon geometry. Non-complete circumferential geometry canadvantageously provide alignment of the balloon void area with acalcified lesion so that the remainder of the vessel cross section canbe safely dilated. This avoids putting excessive force on the hardenedlesion, which in turn puts focused pressure on the wall of the artery atthat site. A nonconcentric stent also may be loaded onto such a deviceto avoid a hardened lesion, while still supporting or reinforcing theremainder of the cross section of the vessel.

The catheter designs also may advantageously allow multiple guide wiresto be used with the device for several purposes, including guiding asecond catheter to a branched, or bifurcated section of an artery.Additional advantageous features include perfusion without therequirement of an internal catheter lumen as well as being compatiblewith devices such as those used for embolic protection. The designs alsoadvantageously provide a device that can be produced as a separatecomponent that can be used with other commercially available catheters,e.g., converting an Over-the-Wire (OTW) catheter to a Rapid Exchange(RX) catheter. The catheter designs can utilize a standard 0.014″ guidewire as well as a hollow tipped-guide wire for tissue and lesionsampling and retrieval.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective side view of a first embodiment of a markercatheter.

FIG. 2 is a perspective side view of an open coil marker attachment.

FIG. 3 is a perspective side view of a closed coil marker attachment.

FIG. 4 is a perspective side view of a closable coil marker attachment.

FIG. 5 is a perspective side view of the closable coil marker attachmentof FIG. 4 with the closable coil being partially opened.

FIG. 6 is an end view of the marker catheter of FIG. 1.

FIG. 7 is a cross-sectional end view of the tubular body/catheter shaftof the marker catheter of FIG. 1.

FIG. 8 is a perspective side view of a marker attachment with astaggered profile.

FIG. 9 is a perspective side view of a marker attachment having areduced diameter wire and constant inner diameters of the coils.

FIGS. 10-12 are perspective side views of a marker attachment withparallel extensions connecting the coils.

FIGS. 13 and 14 are perspective side views of increased flexibilitymarker attachments with alternatively placed extensions connecting thecoils.

FIG. 15 is a perspective side view of a catheter with a radiopaque tubemarker attachment.

FIGS. 16 and 17 are perspective side views of marker attachments withradiopaque tubes and coils.

FIGS. 18 and 19 are perspective side views of marker attachments withradiopaque bands.

FIG. 20 is a perspective side view of a marker attachment with a slottedradiopaque tube.

FIG. 21 is a perspective side view of a catheter with a markerattachment mounted to the distal end of the catheter.

FIG. 22 is a perspective side view of a catheter with a markerattachment mounted to the distal end of the catheter with an attachmentband.

FIG. 23 is a perspective side view of a catheter with an integrallyformed marker attachment.

FIG. 24 is a perspective side view of a catheter with an integrallyformed marker attachment with marker bands.

FIG. 25 is a perspective side view of an integrally formed markerattachment tip.

FIG. 26 is a perspective side view of a dual lumen, integrally formedmarker attachment tip.

FIG. 27 is a perspective side view of the dual lumen attachment tipprior to formation of the coil.

FIGS. 28-30 are perspective side, top, and end views of an embodiment ofa marker attachment with multiple marker coils configured to track aguide wire.

FIGS. 31-33 are perspective side, top, and end views of an embodiment ofa marker attachment with a single marker coil configured to track aguide wire.

FIGS. 34-36 are perspective side views of an embodiment of a markerattachment with a mounting band or tip.

FIGS. 37-39 are top views of a mounting end of marker attachments.

FIGS. 40 and 41 are top and end views, respectively, of one side of aheated compression die for mounting a marker attachment to a catheter.

FIGS. 42 and 43 are top and end views, respectively, of one side of aheating element to contain and heat the compression die of FIGS. 40 and41.

FIG. 44 is a side view of a catheter having a guide wire slot for rapidexchange of the guide wire.

FIG. 45 is a cross-sectional side view of the shaft of the catheter ofFIG. 44 taken at section mark A.

FIG. 46 is a cross-sectional side view of the shaft of the catheter ofFIG. 44 taken at section mark B showing the guide wire slot.

FIG. 47 is a cross-sectional side view of the shaft of the catheter ofFIG. 44 taken at section mark C.

FIG. 48 is a side view of the catheter of FIG. 44 with an optionallyclosed guide wire channel.

FIG. 49 is a cross-sectional side view of the shaft of the catheter ofFIG. 48 taken that at the distal end of the catheter and shown at thepoint where the balloon and the guide wire slot are adjacent to eachother.

FIG. 50 is a side view of a rapid exchange catheter having a guide wirepassage in the catheter shaft wall.

FIGS. 51-54 are cross-sectional side views of the catheter shaft takenat points A, B, C, and D, respectively, of the catheter of FIG. 50.

FIG. 55 is side view of a rapid exchange catheter having a detent orgroove with an option guide passage tube.

FIGS. 56-59 are cross-sectional side views of the catheter shaft takenat points A, B, C, and distal tip, respectively, of the catheter of FIG.55.

FIG. 60 is a side view of a catheter having an embedded guide wirepassage between an inflatable balloon and the catheter shaft.

FIGS. 61-63 are cross-sectional side views of the catheter shaft takenat points A, B, and C, respectively, of the catheter of FIG. 60.

FIGS. 64-71 are various side and cross-sectional shaft views of rapidexchange and marker catheters.

FIGS. 72 and 73 are side and perspective side view, respectively, of amarker catheter formed using a reinforcing wire as a shaft component forpushability, as a radiopaque marker, and as a rapid exchange member.

FIGS. 74-76 are a side and two cross-sectional shaft views,respectively, of a catheter having one or more slots for rapid exchangeof the guide wire and passage of a therapeutic or protective device.

FIGS. 77 and 78 are side and cross-sectional shaft views, respectively,of a rapid exchange catheter having one or more passages in the cathetershaft wall for passage of a guide wire and passage of a therapeutic orprotective device.

FIGS. 79 a, 79 b, and 79 c are a side and two cross-sectional shaftviews, respectively, of a catheter having one or more detents or grooveswith an optional guide wire passage tube and a passage tube for atherapeutic or protective device.

FIGS. 80 and 81 are side and cross-sectional shaft views, respectively,of a catheter having one or more passages in the catheter shaft wall forpassage of a guide wire and passage of a therapeutic or protectivedevice.

FIGS. 82 a-82 h are side and cross-sectional side views of a catheterhaving a slot along its length

FIGS. 83 a-83 g are side and cross-sectional side view of a catheterhaving a slot along its length and protrusions in the slot.

FIGS. 84 a-84 g are side and cross-sectional side views of a catheterhaving a guide tube integrally mounted or firmly attached to a cathetershaft.

FIGS. 85 a-85 g are side and cross-sectional side views of a catheterhaving a slotted guide tube integrally mounted or firmly attached to acatheter shaft.

FIGS. 86 a-86 h are side and cross-section side views of a catheterhaving a longitudinal slot along its length.

FIGS. 87 a-87 j are side and cross-section side views of a catheterhaving one or more guide sections.

FIG. 88 is a cross-sectional side view of a multi-compartment ballooncatheter.

FIG. 89 a is a cross-sectional side view indicating the formation of themulti-compartment balloon catheter of FIG. 88.

FIGS. 89 b-89 e are side views of a multi-diameter balloon for placing astent in the coronary artery at a position distal to the coronaryostium.

FIG. 90 is a cross-sectional side view of the multi-compartment ballooncatheter of FIG. 88 inserted within an obstructed vessel.

FIGS. 91 a-91 g are side and cross-sectional views of a balloon catheterhaving a slotted guide wire/perfusion channel, a marker band, and aballoon with one or more compartments.

FIGS. 92 a-92 f are side and cross-sectional views of a second ballooncatheter having a second implementation of a slotted guidewire/perfusion channel, a marker band, and a balloon with one or morecompartments.

FIGS. 93 a-93 f are side and cross-section views of a catheter thatincludes a peelable guide wire opening.

FIGS. 94 a-94 d are cross-sectional views of a catheter having acollapsible balloon inflation/deflation lumen.

FIGS. 95 a-95 s and 96 a-96 s are examples of specific implementationsof the techniques and features described herein and include specificdetails to enable one of skill in the art to implement the techniquesand features described herein.

FIGS. 97 a-97 e are side and cross-sectional views of a catheter thatincludes one or more guide wire channels and one or more balloons.

FIGS. 98 a-98 d are side and cross-sectional views of a catheter thatincludes a radially extending channel formed in a fold in a balloon andextending from a guide wire channel to a side port in the balloon.

FIG. 98 e is a cross-sectional side view of the catheter of FIG. 98 aand a hollow-tipped guide wire placed within the lumen of a bloodvessel.

FIGS. 98 f and 98 g are a perspective view and an end view of thehollow-tipped guide wire of FIG. 98 e.

FIG. 98 h is a cross sectional side view of the distal end of thehollow-tipped guide wire and a section of plaque.

FIG. 99 a is a side view of the balloon portion of a catheter showinghidden views and a radially extending channel formed in balloon folds.

FIGS. 99 b and 99 c are cross-sectional side views of the balloonportion of the catheter of FIG. 99 a taken along section lines b-b andc-c.

FIG. 99 d is a top view of the balloon portion of the catheter of FIG.99 a.

FIG. 99 e is a side view of a cylindrical member used to form theradially extending channel of FIG. 99 a.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

FIGS. 1-7 illustrate an example of a rapid exchange catheter 100 thatalso can be easily installed over a guide wire or other tubular guidingdevice, or any other catheter that utilizes a guide wire. The rapidexchange catheter can be used in a variety of procedures, includingorthopedic, gastrointestinal, cardiovascular, and radiological. Specificcardiovascular uses include percutaneous coronary transluminalangioplasty (“PTCA”), stent placement, graft deployment (e.g., aorticreplacement or reinforcement), and/or therapeutic infusion. The markercatheter 100 is configured as a balloon catheter and includes a tubularbody 105, a mounting lumen 110, a central lumen 115, a marker attachment120, and an inflatable balloon 125. The tubular body 105 can befabricated from any medical grade polymer, including any well knownpolymer, such as nylon, polyethylene, Pebax™, polyimide, polyamide,polyester, polypropylene, and/or any combination of these or othersuitable materials. The shaft of the tubular body optionally can bereinforced using a polymer, a metal, a metal alloy (e.g., nitinol,stainless steel, Elgiloy™, inconel, 17-7 PH™), and/or any combination ofthese or other suitable materials. The shaft also can be reinforced, orseparately reinforced, using a reinforcing component or technique, suchas one or more wires having a shape that is round, flat or of anothergeometry; multiple tubing layers, with or without a tie, or bondinglayer; a mandrel; a hypotube; by irradiation; using variable wallthickness; and/or any combination of these or by another suitablereinforcing components and techniques. Reinforcing shaft components caninclude a mandrel, a hypotube, or any other article that can be usedinside the shaft, outside the shaft, or be used as the catheter shaftitself, or other configuration. The reinforcing shaft components can bemovable, removable, or fixed. The reinforcement can be along the entirelength, or a partial length at selected locations, and can be used toimprove catheter trackability, pushability, and provide a strain relieftransition between bonded catheter segments. The tubular body 105 can beformed using any of the known methods of fabricating tubular bodies,including extrusion (single or multiple layer), casting, injectionmolding, dip coating, and/or any combination of these methods or otherknown, suitable fabrication processes or methods. The tubular body 105also can be reinforced by using a coil, braid, wrap, combination ofthese reinforcement configurations, or any other suitable process,configuration, or method.

The marker attachment 120 extends from the mounting lumen 110 from thedistal end of the marker catheter 100 (FIGS. 6 and 7) and includes acoil or loop configuration with one or more coils or loops 130. Thecoils or loops 130 are placed apart from each other at a known distanceor distances. For example, if there are more than two coils 130 thefirst two coils can be a first distance apart and the distance betweenthe second and third coils can be a second distance apart. If there areadditional coils, the marker attachment can be configured to haveadditional known distances.

The coils 130 also are open such that a physician can easily place themarker attachment 120 over, and remove from, a guide wire 135 withouthaving to slide the catheter 100 all the way to the proximal end of theguide wire 135 or slide the catheter from the proximal end of the guidewire. The distal-most coil 140 can be open (FIG. 2), closed (FIG. 3), orclosable (FIG. 4). For example, the open coil configuration (FIG. 2) isformed without any closed loop so that the guide wire can be insertedinto the coils. The distal end of the coil can be configured as a bluntend or an end that is turned back towards the distal end of the catheterso that it does not puncture a vessel while sliding along a guide wire.Of course, the distal end and the coil itself can be configured toadvance through a lesion or vessel occlusion based on an advancing forceand a simultaneous rotational or twisting force. The closed coilconfiguration (FIG. 3) may have open coils along its length and a closeddistal coil or closed coils along its length and a closed or open distalcoil. The coil is closed by, for example, soldering the end of the coilto itself, using an adhesive to adhere the end of the coil to itself, orby forming a micro loop at the end such that it can be positioned aroundthe coil. If the coils 130 are closed, the guide wire is insertedthrough the coils by inserting the proximal end of the guide wirethrough the coils. This configuration ensures that the marker attachment120 will not release from the guide wire. The closable coil (FIG. 4) isformed by bending the coil such that it contacts itself but can beflexibly bent to open the coil (FIG. 5). In this manner, the physiciancan easily mount the marker attachment or remove the marker attachmentfrom a guide wire at any position along the guide wire's length. Themarker attachment can be fabricated from a flexible metal, polymer, orcombination. To visualize the marker attachment under fluoroscopy, themetal or polymer must be radiopaque. For example, the polymer can becompounded with any known radiopaque additive or material, as describedabove, and as is well known in the art of catheter design andfabrication. A radiopaque material may be deposited, or applied to thecoil using ion deposition, sputter coating, spraying, dipping, or anycombination of these or other suitable methods. The outer diameter ofthe coils 130 also can vary along the length such that each coil has adifferent outer diameter and can be used to gauge the diameter of, forexample, a lesion. As illustrated in FIG. 4, the proximal most coil canhave a first outer diameter and the distal most coil can have a second,smaller outer diameter. The marker catheter can be advanced into thelesion until it cannot be advanced further because one of the two ormore coils reaches a diameter of the lesion that is narrower than theouter diameter of one of the coils.

Referring to FIG. 8, in another embodiment of the marker attachment, thecoils 130 can be arranged such that each marker attachment is formedfrom one or more extensions 145 connecting one or more coils. The coilscan be of decreasing inner and outer diameter such that consecutiveextensions 145 are staggered inwardly or outwardly in a step-wisemanner. If the outer diameter of the individual coils 130 is known,advancing the marker attachment into the lesion will permit thephysician to size the inner diameter of the lesion based on which coilis unable to proceed further into the lesion. Moreover, because thecoils 130 are spaced apart known distances, the physician will be ableto gauge the length of the lesion, as well as the inner diameter of thelesion.

Of course, the coils 130 all can be of the same outer and inner diameterwith an inner diameter that is slightly larger than the outer diameterof the guide wire, and the marker attachment material being made of athin diameter metal or polymer wire or tube. In this manner, the markerattachment has a minimized profile, optionally less than the outerdiameter of the catheter to which it is attached.

Referring to FIG. 9, in another embodiment, the marker attachment 120can be fabricated from a wire or tube that has been drawn to have adecreasing diameter along its length. The marker attachment can beformed, for example, by using a nitinol or other shape memory orsuperelastic wire or tube that can be wrapped around a constant diametermandrel and heat formed into that configuration using techniques thatare well known in the art for fabricating articles from shape memory orsuperelastic metals such as nitinol. The marker attachment embodiment ofFIG. 9 will have coils 130 having a constant inner diameter but achanging outer diameter along its length, for example, an outer diameterthat is decreasing from the proximal end to the distal end of the markerattachment 120.

Other configurations and embodiments of the marker attachment 120 areillustrated in FIGS. 10-14. FIGS. 10-12 illustrate embodiments of markerattachments with parallel extensions 145 connecting the coils 130. Themarker attachment 120 can be formed by taking a single wire or tube,such as a nitinol wire or tube, and wrapping coils 130 separated byextensions 145 along the mandrel's length. At the distal most coil 130,the wire or tube can be reversed in direction to form extensions 145that are parallel to the already formed extensions and coils 130 thatare adjacent to the already formed coils (FIG. 9). Alternatively, thewire or tube can be reversed in direction to form coils 130 that areadjacent to the already formed extensions and extensions that areadjacent to the already formed coils. These techniques can be selectedto adjust the flexibility of the marker attachment to track a guide wireor guiding device. The marker attachment then can be heat formed intothat configuration using techniques that are well known in the art forfabricating articles from shape memory or superelastic metals such asnitinol.

FIGS. 13 and 14 illustrate embodiments of marker attachments 120 thathave alternatively placed extensions 145. The marker attachments ofFIGS. 13 and 14 can be formed, for example, by wrapping a wire or tubeone and one-half times around a mandrel and then forming an extension145, wrapping the wire or tube one and one-half times around themandrel, and so on until the desired number of coils 130 and extensions145 are formed. This configuration provides increased flexibility of themarker attachment. Although FIGS. 13 and 14 are shown with the innerdiameter and the outer diameter of the coils 130 being the same, the canbe varied to use any of the configurations described above for providinga gauge of the inner diameter and the length of the lesion into whichthe marker attachment is inserted or passed.

Referring to FIGS. 15-22, the catheter 100 can be implemented with amarker attachment 120 that includes a radiopaque tube 150 mounted to theextension 145. The radiopaque tube 150 can be a metal or polymer tubehaving an inner diameter, an outer diameter, and a channel passingbetween a pair of openings. This marker attachment tracks a guide wiresmoothly and also provides rapid exchange for the physician. The innerdiameter, the outer diameter, and the length of the radiopaque tube 150can be sized according to any of the configurations described above. Forexample, the inner diameter of the radiopaque tube can be slightlylarger than the inner diameter of the guide wire over which it will betracked. The outer diameter of the radiopaque tube can be constant orvaried. For example, the outer diameter of the tube can graduallytransition or use step transitions to go from a first known, smallerdiameter at the distal end to a second known, larger diameter at theproximal end. This will help to gauge the length and inner diameter of alesion. The tube also can be of a known length to provide a gauge tosize the length of a lesion.

One end of the extension 145 can be mounted on the outer surface of thetube 150, the inner diameter of the tube, or to the wall surface formedbetween the inner and outer diameters. Of course, the extension 145 andthe tube 150 can be formed as a single piece, for example by casting,machining, or other material removing operation, such as etching orelectron discharge machining. The extension 145 and/or tube 150 also canbe fabricated from a radiopaque polymer that has been loaded with aradiopaque additive or material.

Various configurations of the radiopaque tube 150 and the coils 130described above are possible. For example, the marker attachment can beformed with a single coil 130 and a pair of radiopaque tubes 150 (FIG.16). The coil can be positioned between or on either side of the tubes.The marker attachment also can be formed with a single coil (FIG. 16)and a single radiopaque tube 150 (FIG. 17). The radiopaque tube also canbe fabricated without a complete circumference, for example, as aslotted radiopaque tube. For example, a percentage of the circumferenceof the tube can be open with a slot 160 so that, for example, a guidewire can be pressed through the slot 160 into the channel in the tube.This facilitates rapid exchange of the guide wire (FIG. 20). Althoughthe term channel is used throughout this application to refer to apassage way with an opening along at least one portion of the passageway, the term channel also encompasses a slot, groove, opening, detent,cross-sectional voids, or other configurations that have do not have acomplete circumferential closure at least at one potion along the lengthof the passage way.

If the extension 145 and the tube 150 are formed from a non-radiopaquematerial, such as a polymer without radiopaque additives, radiopaquegauge or marker bands 155 can be placed along the length of theextension 145 at known distances so that they can be visualized underfluoroscopy (FIG. 18). The extension also can be formed without the tube150 and use just the marker bands 155 mounted on the flexible extension145 (FIG. 19).

The marker attachment using a radiopaque tube, as well as the othermarker attachments described herein, can be used on any tubular device.In the cardiovascular field, the marker attachments can be used, forexample, on guide catheters, diagnostic catheters, infusion catheters,etc. As illustrated in FIGS. 21 and 22, the marker attachment with theradiopaque tube 150 is mounted to a catheter that does not have aninflatable balloon. The marker attachment can be mounted to the innersurface, the outer surface, the edge wall, or into the wall or betweenlayers of the catheter (FIG. 21). For example, the marker attachment canbe formed as part of a tip in a first operation and that tip is fused tothe distal end of the catheter in a subsequent operation. The markerattachment also can be mounted to the catheter by using an attachmentband 170 to hold the extension 145 to the catheter 100.

Referring to FIGS. 23 and 24, a catheter 200, which may be implementedas an inflatable balloon catheter, a guiding catheter, a diagnosticcatheter, an infusion catheter, etc., includes a shaft 205 and a coiledtip 210. The tip is coiled to track a guide wire with the capability ofbeing rapidly exchanged because of the coil shape. The coiled tip 210 isformed separately and subsequently attached to the shaft or formedintegrally with the shaft 205. For example, to form the tip integrally,the distal end of the shaft is inserted into a hot die to compress andshape the tip into a coiled shape. The heat and compression impart ausable balance between flexibility and stiffness on the coiled tip sothat the coiled tip will track a guide wire but not be so flexible thatit falls off and not be so stiff that it damages the tubular vessel inwhich it is inserted. The coiled tip also can be formed by drawing downthe shaft over a mandrel to impart the coiled shape. The coiled tip alsocan be formed by placing a shaped thin wire or tube within the distalend of the shaft and heating the distal length of the shaft to shrink itover the thin wire or tube so that the distal end of the shaft isimparted the shape of the wire or tube. The wire or tube can be madefrom, for example, a shape memory or superelastic metal, such asnitinol. The wire or tube can be straight at the first coolertemperature in which it is inserted into the shaft and then when theshaft is heated, for example, by reaching body temperature, the wire ortube will regain its initially formed coiled-shape, which will beimparted to the shaft. An inflatable balloon 213 optionally can bemounted to the shaft. Optionally, marker bands 215 can be placed aroundthe coiled tip 210 after it is formed (FIG. 24). The distance betweenthe bands 215 can be known and calibrated so that it can be used togauge lengths and positions within the tubular vessel in which thecatheter 200 is inserted.

As illustrated in FIGS. 25-27, the coiled tip 210 can be formed as aseparate tip that is formed to be coiled using any of the methodsdescribed above, and then fused to the catheter using any of thewell-known fusing techniques, such as hot die fusing, thermal fusing,laser fusing, and/or RF-induction fusing or heating. The tip can beformed with a dual lumen and the upper lumen 225 cut away so that anopening 230 of that lumen remains (FIG. 27). The lower lumen 235 then isformed as a coil and then fused to the catheter. In this manner, thecatheter lumen remains open along its entire length, including throughthe tip.

Referring to FIGS. 28-39, various embodiments, configurations, andfurther details of the marker attachments described above are shown. Forexample, FIGS. 28-30 show a marker attachment 120 with coils 130 thatare open such that a guide wire can easily be inserted into each coil.The coils 130 are separated from each other by known distances. Thisembodiment of the marker attachment has a common, minimized outerdiameter and an inner diameter configured to smoothly and tightly tracka guide wire.

Referring to FIGS. 31-33, a marker attachment 120 can be formed with asingle extension 145 and a single coil 130. The coil can be flexiblyclosed so that a guide wire can be inserted through the inner diameterof the coil or the coil can be flexibly opened so that the guide wirecan be inserted and removed through the slot formed in that manner.

Referring to FIGS. 34-36, the marker attachment 120 can be formed with amounting tip or mounting band 250 that is integral with the extension145 and used to mount the marker attachment to the catheter. The tip orband 250 can be flared down or of a constant outer diameter. The coilscan be formed such that a guide wire can be inserted into an opening inthe coils so that the marker attachment and catheter will track theguide wire. The tip or band 250 can be adhered to the catheter tip by anadhesive or by compression of the band. For example, the band can beformed with an opening or slot to that it can be compressed together tobe retained in place on the catheter.

Referring to FIGS. 37-39, the marker attachments described above can beconfigured to have mounting ends 275 that enhance attachment to acatheter. For example, referring to FIG. 37, the mounting end 275includes extensions 280 on the edges and projections 285 on the sides.When the mounting end is mounted with the catheter, for example, in themounting lumen, the extensions and projections further secure the endwithin the mounting lumen. Referring to FIG. 38, the mounting end 275includes openings 290 through which an adhesive can flow or polymer inthe mounting lumen can be compressed to further secure the end withinthe mounting lumen. Finally, referring to FIG. 39, the mounting end 275can have a roughened or dimpled surface 295 that enhances adhesion. Theextensions 280, projections 285, openings 290, and surface 295 can beformed using any known technique, including stamping, cutting,machining, etching, electron discharge machining (“EDM”), laser cutting,etc.

Referring also to FIGS. 40-43, the mounting ends 275 of the markerattachments 120 can be mounted in the mounting lumen 110 (FIG. 7) byusing a split die system 300. Of course, many other conventional systemsare known and this is merely one exemplary method. The split die system300 includes a heated half die 305 and a heating half die retainingelement 310. The die and element can be formed as an integral unit.However, as illustrated in FIGS. 40-43, which shows one half of thesystem 300, the die and element also can be separated formed and mountedtogether. The half die 305 includes a tapered channel 315 that includesa first length 316 and a second tapered length 317. The die 305 receivesthe shaft 105 with the mounting attachment 120 inserted. The half die305 also includes male and female mating sections 320 for mating withopposite mating sections of the other half die 305, and mating sections325 for mating with opposite mating sections in the die element 310.These can be configured as channels that slide over rails. The half diecan be made of, for example, a heatable material with a nonsticksurface, such as Teflon™ (i.e., polytetrafluoroethylene (“PTFE”)). Thedie element 310 includes a channel 330 configured to retain the half die305 and rails 335 configured to keep the die in position. The elementalso includes male and female mating sections 340 for mating with theother half of the element during compression. The element can be heatedusing any conventional means. In use, the catheter with markerattachment inserted is placed in the first length 316 and the two diehalves 305 are closed together to compress and heat the catheter. Thecatheter is then manually or automatically advanced such that the distaltip is advanced into the tapered length 317. This forces the plastic ofthe catheter to be compressed around the marker attachment's mountingend 275 (FIGS. 37-39), which secure the marker attachment to thecatheter. The die halves then are separated and the catheter removed. Aninflatable balloon can be attached to the catheter before or after thisoperation, if desired.

Referring to FIGS. 44-48, although the catheter 100 described above canbe configured with a marker attachment to track a guide wire and beeasily and rapidly exchanged, a catheter 400 also can be configured totrack a guide wire, and be easily and rapidly exchanged without the useof a marker attachment or marker system at all. For example, thecatheter 400 includes a hub 405, a shaft 410, a slotted, open channel415, an inflatable balloon 420, and an inflation lumen 425 for inflatingthe balloon 420. A guide wire 425 can be inserted and passed through theslotted, open channel 415.

In general, the catheter 400 has a non-concentric ballooncross-sectional profile, with the slotted channel 415 (including andbeing formed to include a guide wire channel 417 and a guide wire slot418) located on the outside of the main shaft 410, at the longitudinalballoon seam, or generally in the area where the balloon is in contactwith the outer surface of catheter shaft 410, even when the balloon isinflated. The guide wire slot or groove 415 can have an internal,concave profile. The open groove or slot 415 is smaller than thediameter of the guide wire, allowing the wire to move freely within thechannel, but without coming out of the slot or groove unless it ispulled out by the physician. The wall of the slot 415 can be somewhatflexible so that the guide wire can be easily inserted through andremoved from the channel 415 to easy exchange of the catheter over theguide wire.

Moreover, in a modification of the catheter 400, a conventional markerband can be optionally placed around the slot 415 at its distal most endto provide a highly visible radiopaque indicator and give a senseassurance that the guide wire is less likely to come out of the slotunless the physician slidably removes the guide wire through the marker.Of course, the marker band is optional in this configuration and thecatheter 400 will be extremely functional and usable for easy and rapidexchange of guide wires without the marker band. In anothermodification, the guide wire channel or slot (415, 417, and 418) may bepositioned along a detented longitudinal area of the balloon 420.

The guide wire 425 also may be inserted into the proximal end of theguide wire slot 418, or, through the top opening of the slot or grove,and then snapped or positioned into place. In this manner, the concavegeometry and size of the interior of the groove or slot prevents theguide wire from falling out.

The catheter 400 is formed using conventional techniques as are known inthe art of catheter fabrication. For example, the shaft can befabricated by pressure extrusion or tubing extrusion such that the tubehas a cross-sectional profile of the inflation lumen 425 and the channel415. The proximal end of the channel 415 then is removed such that onlythe distal end of the catheter has the channel 415. The inflation lumen425 then is closed to have a taper (FIG. 47) and a balloon next isformed on the shaft, as illustrated in cross-section in FIG. 46.

Of course, the catheter can be formed by extruding a single lumen tubehaving the cross-sectional profile of FIG. 45, extruding a tube havingthe lumen of FIG. 46 (without the balloon), and then fusing the twotubes together. Such fusing techniques are well known in the art andinclude hot die compression fusing, directed hot air, and RF-inductionfusing.

As illustrated in FIGS. 48 and 49, the slot can be open, or can be openfor most of the length and completely closed only for a short portion.

Referring to FIGS. 50-54, a catheter 500 includes a hub 505, a firstshaft segment 510, a second shaft segment 515, a third shaft segment520, and fourth shaft segment 525. The first shaft segment 510 includesan inflation lumen 530. The second shaft segment 515 includes theinflation lumen 530 and guide wire lumen 535. The third shaft segment520 includes the inflation lumen, the guide wire lumen 535, and aninflatable balloon surrounding its outer circumference. Finally, thefourth shaft segment 525 includes the guide wire lumen 535 opening tothe distal end of the catheter offset from the center of the catheter,or centered with the catheter, and the inflation lumen 530 is sealedclosed by, for example, heating, compressing, and optionally pulling thetip or distal end in a tapered die and/or with the use of an adhesive toclose the distal end of the inflation lumen. In this configuration, theguide wire passes through a first proximal opening 540 in the guide wirelumen and exits through a second distal opening 545 in the guide wirelumen. The length of the guide wire lumen can be less than, for example,20, 15, or 10 cm. It can be, for example, less than 5 cm, and can evenbe approximately two cm in length. Moreover, the proximal opening 540can be less than 20, 15, or 10 cm from the balloon, such as, forexample, approximately 0.5 cm from the balloon, or between 0.5 cm and 10cm from the balloon. The first segment 510 can be formed separately fromthe other segments (515, 520, 525) and then fused or otherwise attachedto the second segment 515 using known methods from the catheter art.

Referring to FIGS. 55-59, another embodiment of a radiopaque markercatheter 550 that can be rapidly exchanged over a guide wire includes ahub 555, a first shaft segment 560, a second shaft segment 565, a thirdshaft segment 570, and a fourth shaft segment 575. The first shaftsegment, the second shaft segment, and the third shaft segment includean inflation lumen 580. The third shaft segment 570 optionally includesa detent or longitudinal groove 583 in which the guide wire 425 can passor be received during balloon inflation to prevent excessive force onthe wire against the vessel wall. The formation of such longitudinaldetents or grooves is disclosed and taught by Houser (U.S. Pat. No.5,865,801), which is incorporated in its entirety herein by reference.The distal end of the catheter, the region below the balloon, and/or theproximally of the balloon, also could include a conventional marker band585 that encircles the groove 583 and under which the guide wire couldpass to advance the catheter along the guide wire. In this embodiment, aballoon 590 is non-concentrically placed around the catheter shaftsegment 570 such that the groove is exposed. A tube 593 optionally canbe mounted to the groove to provide a passage for the guide wire. Thetube can be configured according to any of the concepts and techniquesdescribed above and can be configured as a radiopaque marker or gauge.This tube receives the guide wire during inflation to prevent it frombeing pressed against the vessel wall under the extreme pressures ofballoon inflation.

Referring to FIGS. 60-63, a rapid exchange catheter 600 includes a hub605, a first shaft segment 610, a second shaft segment 615, a thirdshaft segment 620, an inflatable balloon 625, and a guide wire lumentube 630. An inflation lumen 635 passes through the first shaft segment,the second shaft segment, and the third shaft segment. The tube 630starts proximally of, and ends distally of, the balloon 625. The distalend of the catheter after the balloon also can be formed with a groovethrough which the guide wire passes. The groove can be slotted, asdescribed above to better retain, remove, and exchange the guide wire.This also provides a centering of the guide wire when it exits thecatheter.

In other embodiments of the rapid exchange catheter, a guide wire lumencan be formed inside the catheter tubing wall rather than as a separatelumen. The guide wire lumen can be, for example, 0.5 cm long or less,and pass under a distal-most marker band. Where the catheter includesthe guide wire being compressed between the balloon tubing and thevessel wall, longitudinal grooves, detents, valleys, cross-sectionalvoids, or other similar configurations in the balloon that would allowthe wire to lay in a channel or groove-like region, and not be forcedinto the vessel wall under the pressures of balloon inflation.Additionally, the guide wire lumen can be formed separately as aseparate piece that then is bonded under the balloon, and may or may notoptionally continue or extend to the tip of the catheter. Finally, thecatheter may be formed from multi-lumen tubing with one or more lumensremoved at specific areas along the catheter length.

The catheter shafts described above can be formed from any biocompatiblemedical grade polymer, such as nylon, polyethylene, Pebax®, polyimide,polyamide, polyester, polypropylene or any other combination of these orother suitable materials. The shaft can be reinforced to provide, forexample, increased pushability, with a polymer or polymers, metals,metal alloys (such as nitinol, stainless steel, Elgiloy®, inconel, 17-7PH™), or any combination of these or other suitable materials.Reinforcing shaft components can include a mandrel, a hypotube, or anyother article that can be used inside the shaft, outside the shaft, orbe used as the catheter shaft itself, or other configuration. Thereinforcing shaft components can be movable, removable, or fixed. Thereinforcement can be along the entire length, or a partial length atselected locations, and can be used to improve catheter trackability,pushability, and provide a strain relief transition between bondedcatheter segments. Other shaft reinforcing components include wire ortube (shaped to be round, flat, or any other geometry); multiple tubinglayer(s), with or without a tie or bonding layer; a mandrel; a hypotube;by irradiation; by using a variable wall thickness; and/or anycombination of these or other suitable component(s). The balloonmaterial can be compliant or non-compliant. Examples of compliantballoon materials include but are not limited to polyethylene;polyurethane; Tecoflex®; or any combination of these or other suitablematerials. Examples of non-compliant balloon materials include nylon;polyester (PET—polyethylene terephthalate, or other); Pebax®; polyimide;polyamide; or any combination of these or other suitable materials.

Radiopaque marker bands or marker attachments can be formed form gold,platinum/iridium, tantalum, or any combination of these or othersuitable materials.

The proximal adapter, adapters, or hub can be configured as a Luer orother type fitting to enable connection to an inflation source and befabricated from, for example, polycarbonate, polyurethane, polyester, orany combination of these or other suitable materials.

The catheter shaft can be fabricated by extrusion (e.g., single ormultiple layer extrusion, tubing extrusion, pressure extrusion),casting, injection molding, dip coating, or any combination of these orother suitable methods or processes. The catheter shaft can be formed asmultiple shaft pieces with tubing bonding, balloon to shaft bonding, andshaft to proximal adapter bonding. The bonding can include thermal(including RF-induction, forced heated air, laser, etc.), adhesive,ultrasonic welding, molding, or any combination of these or othersuitable methods and processes.

To reinforce the shaft, the methods and materials usable include coilsand coiling, braids and braiding, wraps and wrapping, or any combinationof these or other suitable methods and materials. These reinforcementscan be positioned or located inside, outside, within the shaft, inbetween, or any combination of these on the catheter.

The balloon fabrication process includes heat forming, cold forming, orany combination of these or other suitable methods and processes.

The catheter or the various parts of the catheter can be coated (staticor active eluding) to be lubricious, anti-thrombogenic, therapeutic, orany combination of these or other suitable coating types, materials, andobjectives. For example, the marker attachments and coils can be coatedwith a low durometer polymer to increase the softness of the attachmentfor less trauma during interaction with lesions.

Alternative applications for the rapid exchange feature includepercutaneous transluminal angioplasty (“PTA”), stent and graftdeployment catheters, therapeutic infusion, and any other catheter ormedical device that utilizes a guide wire or guiding member.

The catheter size ranges for the catheters described above may include acatheter shaft having different proximal and distal diameters in therange of approximately 2 to 5 French, or greater. The balloon may havean inflated diameter that is between approximately 1.5 and 4.5 mm, orgreater or less, and may be tapered. The length of the balloon may beapproximately 10 to 40 mm, or greater or less. The guide wire may beapproximately 0.014″ diameter, although larger and smaller guide wirediameters are envisioned depending upon the application.

Additional views and embodiments of rapid exchange and marker cathetersare illustrated in FIGS. 64-71. These provide rapid exchange of a guidewire and optional marker bands for sizing and gauging dimensions of alesion. Moreover, referring to FIGS. 72 and 73, the marker attachment120 can be formed from a long wire or tube 700 that is removably orpermanently fixed in the mounting lumen of the catheter. If the wire ortube is formed from a rigid material, it will improve the pushability ofthe catheter in which it is installed. The wire or tube can be hollowand have a distal opening and a proximal opening, and can be used totailor the stiffness and/or to inject a diagnostic and/or therapeuticagent or fluid, such as a radioactive agent, a gene therapy agent, orother biological or pharmacological agent. Moreover, arigidity-imparting member, such as a mandrel, can be inserted in thehollow wire or tube to cause a change in stiffness of the wire or tubeand, consequently the stiffness of the catheter. In addition, thisconfiguration will reduce the manufacturing steps because it will beeasier to mount the long wire or tube rather than the short mounting end275 (FIGS. 37-39).

Referring to FIGS. 74-87, the catheters illustrated in FIGS. 44-63 alsocan be configured to provide perfusion of distal tissue during ballooninflation because these catheters include a slot or channel (415, 593)or lumen (535, 630) that provides an inlet for the blood flow proximalto the balloon and an outlet for the blood flow distal to the balloon.Moreover, these catheters can be used to deploy, position, and/or guide,in addition to a first guide wire, a second guide wire or other device,such as an embolic trap or embolic catching device 700 for deployment inthe vessel distal to the balloon during angioplasty. In this manner,when the balloon is in place, the embolic trap 700 can be deployedthrough the channel or lumen, opened, and then the balloon can beinflated. Any embolic material created during the balloon inflation willbe captured by the embolic trap 700 and will be removed from the vesselwhen the balloon catheter and embolic trap are removed. For example,referring specifically to FIGS. 74-76, a catheter 710 is configuredsimilarly to the catheter 400 of FIGS. 44-47 and includes a slotted,open channel 715 (FIG. 75) or a pair of slotted open channels 715 (FIG.76). The slots provide a passage way from the proximal end to the distalend of the balloon. The channel(s) 715 provide a passage way for distalperfusion during balloon inflation, a first and/or second guide wire425, a therapeutic or diagnostic device, such as an embolic trap 700.Optionally, one or more tubes can be positioned within the slot or slots715 to more further define the passage way. Referring specifically toFIGS. 77 and 78, a catheter 730 is configured similarly to the catheter500 of FIGS. 50-54 and includes a pair of passage ways 535 passinglongitudinally through the wall of the catheter shaft. One passage waycan be used to deploy or track a guide wire and the other to carry,deploy, or position a therapeutic or protective device, such as theembolic trap 700. The other passage way also can be used to deploy ortrack a second guide wire, or a therapeutic or diagnostic device. Thechannels or passage ways 715 can be, for example, grooves, slots,detents, distal coils, or combination of these or other suitablechannel. The channels or passage way may be interrupted, full catheterlength, placed distal only, or partially along the length of thecatheter (e.g., the distal end of one of the channels or passage waysmay end before the end of the catheter—under or near the balloonregion). As described in greater detail below, a first guide wire maythen be able to exit the channel or passage way from a location otherthan the distal end (e.g., tip) of the catheter—for example, through avoid or opening through the balloon—while enabling a second guide wireto exit a second channel or passage way at the distal end of thecatheter. The guide wire may be positioned into a side branching vessel,to direct another catheter (e.g., for PTCA, stent deployment, or other)into the side branch. Such a placement can be particularly beneficialwhen deploying a second stent (e.g., a bifurcated stent segment or otherconfiguration of a stent) or other therapeutic or diagnostic device toor around the treatment site.

Referring specifically to FIGS. 79 a, 79 b, and 79 c, a catheter 750 isconfigured similarly to the catheter 550 of FIGS. 55-59 and includes oneor more detents or longitudinal grooves 755 in which one or more tubes760 can be mounted to provide a passage for the guide wire 425, theembolic trap 700 or any other therapeutic, diagnostic, or protectivedevice to be carried, deployed, or positioned. For example, one tube 760can be used to track the guide wire 425 and the other tube 760 can beused to carry, deploy, and position the embolic trap 700. The tubes 760can be configured according to any of the concepts and techniquesdescribed above and can be configured as a radiopaque marker or gauge.These tubes receive the guide wire and a portion of the length of theembolic trap device 700 during inflation to prevent it from beingpressed against the vessel wall under the extreme pressures of ballooninflation.

Referring specifically to FIGS. 80 and 81, a catheter 775 is configuredsimilarly to the catheter 600 of FIGS. 60-63 and includes one or morelumen tubes 780. The tubes 780 start proximally of, and end distally of,the balloon. One of the lumen tubes 780 can be used to deploy or track aguide wire and the other to carry, deploy, or position a therapeutic orprotective device, such as the embolic trap 700. The distal end of thecatheter after the balloon also can be formed with one or more groovesthrough which the guide wire passes. The groove can be slotted, asdescribed above to better retain, remove, and exchange the guide wireand/or the embolic trap. This also provides a centering of the guidewire and embolic trap where it exits the catheter. The techniques anddevices for providing a method of deploying an embolic device or trap700 can be applied to other types of catheters as well, such asdiagnostic, therapeutic, guiding, and other types of catheters.

Referring to FIGS. 82 a-82 g, a rapid exchange catheter 800 includes aslot 805 along its length. The slot extends from any position proximalof an inflatable balloon 810 to a position distal of the inflatableballoon, and is configured to accept and removably retain a guide wire135. The guide wire can pass under the balloon as illustrated in FIG. 82e or in an opening 815 between a pair of non-circumferential balloons820, as illustrated in FIG. 82 g. The catheter 800 can be extruded as adual lumen shaft having an inflation lumen 825 and a guide wire channel830 that is modified to be the slot 805 (FIG. 82 b). The slot 805 isformed to have an opening 835 that has a width that is narrower than awidth of the guide wire channel 830. For example, the slot 805 can beformed from a pair of longitudinal edges 840 which run the length of theslot. The slot can be formed by a cutting operation or other materialremoval operation. If the catheter 800 is formed from a flexiblepolymer, the longitudinal edges will be flexible enough to flex tointentionally receive and intentionally remove the guide wire 135 butthe combination of the flexibility and the width of the slot will besuch that the guide wire will not easily pass through the slot withoutthe physician applying force to pull it through. The distal end of theslot may open to the side of the catheter or to the distal tip of thecatheter. In either configuration, the catheter will track the guidewire and can be rapidly exchanged because the guide wire can be pulledthrough the slot until it exits the slot at a point just proximal of theballoon.

The slot can be formed to start adjacent to the hub, adjacent to theinflatable balloon, or at any position in between. For example, if theslot starts adjacent to the hub, the pushability and the trackability ofthe catheter 800 may be perceived to be better. Then, to remove thecatheter from the guide wire, the guide wire can be pulled out of theslot until it is just proximal to the balloon. If the slot 805 starts inthe vicinity of the balloon, that portion of the channel 830 between thehub and the slot can have a mandril inserted within to improvepushability and rigidity, as necessary or desirable. The mandril can bemovable, removable, or fixed.

The catheter 800 can be modified to have slot 840 with a narrow width orwider width. For example, the distance between the longitudinal edges840 can be less than 0.005 inches. If the catheter 800 is made from aflexible polymer, the edges will nonetheless be flexible enough suchthat the guide wire 135 still can be received or removed through theslot. The slot also can be wider so that the distance between the edges840 is slightly less than the diameter of the guide wire, for example,0.005 inches less than the diameter of the guide wire. In this mannerthe guide wire will still be retained within the slot but will be evenmore easily received and removed through the slot.

The channel 835 can be formed to have any cross-sectional profile to theextent that a guide wire can be at least partially retained within thechannel. Moreover, the cross-sectional area of the channel only needs tobe large enough to receive at least a part of the guide wire.

Referring to FIGS. 83 a-83 g, a rapid exchange catheter 850 includes aslot 855 along at least a portion of its length and protrusions 860 thatextend from opposite longitudinal edges 865 of the slot. The protrusions860 can be offset (FIG. 83 a) or aligned (FIG. 83 g) and can becontinuous along the length of the slot or discontinued under theballoon 810 (FIG. 83F). The catheter is formed by, for example,extrusion and includes a pair of lumens 825 and 830. The lumen 830 isconverted to a channel by forming a slot into the lumen. The slot 855 isformed by, for example, removing wall material of the catheter to forman opening into the lumen 830. The material can be removed in short orlong segments, depending upon whether the protrusions 860 are to beoffset or aligned. The protrusions then can be formed by cutting them inthe center between the edges 865 (aligned protrusions) or adjacent tothe edges (offset protrusions).

The protrusions 860 are flexible enough to allow the guide wire to beinserted and removed between them (aligned protrusions) or between theprotrusion and the longitudinal edge 865 (offset protrusions). In thismanner, the guide wire can be easily removed from the catheter in arapid exchange procedure.

The slot 855 can be formed to start adjacent to the hub, adjacent to theinflatable balloon, or at any position in between. For example, if theslot starts adjacent to the hub, the pushability and the trackability ofthe catheter 850 may be perceived to be better. Then, to remove thecatheter from the guide wire, the guide wire can be pulled out of theslot until it is just proximal to the balloon. If the slot 855 starts inthe vicinity of the balloon, that portion of the channel 830 between thehub and the slot can have a mandril inserted within to improvepushability and rigidity, as necessary or desirable.

The catheter 850 can be modified to have slot 855 with a narrow width orwider width. For example, the distance between the longitudinal edges865 and the protrusions 860 can be less than approximately 0.005 inchesor more than approximately 0.005 inches. If the catheter 850 is madefrom a flexible polymer, the edges will nonetheless be flexible enoughsuch that the guide wire 135 still can be received or removed throughthe slot. The slot also can be wider so that the distance between theedges 865 and protrusions 860 is slightly less than the diameter of theguide wire, for example, 0.005 inches less than the diameter of theguide wire. In this manner the guide wire will still be retained withinthe slot but will be even more easily received and removed through theslot.

The channel 835 can be formed to have any cross-sectional profile to theextent that a guide wire can be at least partially retained within thechannel. Moreover, the cross-sectional area of the channel only needs tobe large enough to receive at least a part of the guide wire.

Referring to FIGS. 84 a-84 g, a rapid exchange catheter 900 includes aguide tube 905 integrally mounted or firmly attached to a catheter shaft910. The catheter shaft 910 includes an inflation lumen 825 to inflatean inflatable balloon 810. The guide tube 905 includes a guide wirechannel 830 through which a guide wire can pass and/or which can be usedas perfusion channel. The guide tube 905 may be separately extruded andthen mounted to the catheter shaft (FIGS. 84 c and 84 d). The guide tube905 also may be integrally formed with the catheter shaft, for exampleby extrusion, and then the proximal most portion of the guide tuberemoved in a material removal operation, as is well known in theextrusion and plastic fabrication arts (FIGS. 84 f and 84 g). The guidetube 905 can pass under the balloon 810 and extend to the distal tip ofthe catheter, as illustrated in FIG. 84 a. The guide tube also can endproximally of the balloon 810 and then the guide wire could passunderneath or on top of the balloon. The guide tube also can be mountedto the catheter such that only the proximal end and the distal end ofthe tube are mounted to the catheter, using an adhesive for example, andthe middle section of the tube are not physically attached to thecatheter. In this manner, if the proximal end and the distal end of thetube are outside of the ends of the balloon, the balloon can be mountedunderneath the tube such that the balloon forms a fold up and around thetube. If the tube additionally includes a side port opening, a guidewire can be passed through that opening to access a side branch of avessel. Moreover, a radially extending channel can be formed in thefolds of the balloon, as described herein, and that channel used toguide the guide wire to the side branch. The guide tube also can extendpart way or all the way underneath the balloon but then terminate suchthat the distal tip of the catheter 900 has a smaller diameter.

By having a short guide tube 905, the catheter 900 can be easily andrapidly removed and exchanged from the guide wire 135. Moreover, theguide tube 905 can be fabricated to have a slotted configuration, asdescribed above with respect to FIGS. 82 a-82 h and FIGS. 83 a-83 g, orwith any of the configuration described below (FIGS. 85 a-85 g, FIGS. 86a-86 f, or FIGS. 87 a-87 g).

Referring to FIGS. 85 a-85 g, a rapid exchange catheter 920 includes aslotted guide tube 925 and a catheter shaft 930 upon which the guidetube is integrally mounted or firmly attached. The slotted guide tube925 includes a slot 935 that opens into a channel 830 and is formed byan upper edge 940 and a lower edge 945. To insert the guide wire 135into the channel 830, the guide wire is pressed lengthwise of end firstbetween the two edges 940 and 945. The distance or clearance between theedges may be less than the diameter of the guide wire such that guidewire must be forced between the edges, whether the guide wire is beinginserted or removed from the channel 830. Once the guide wire is withinthe channel 830, the edges must be separated to remove the guide wire.

The slotted guide tube 925 may extend distally from the balloon a shortdistance, all the way to the distal tip, or not at all. The tube 925 mayextend proximally from the balloon 810 a short distance, all the way toa position adjacent to the hub, or a position in between. As such,because the guide wire can be removed from the channel 830 at any pointalong its length, the length of the guide tube can be any length and notadversely affect the ability of the physician to remove the guide wire.Thus, the length of the guide tube can be tailored to beneficiallyaffect other characteristics of the catheter 920 as needed.

The slotted guide tube 925 may be formed as a separated extruded tubethat then is firmly attached to a separated extruded catheter shaft 930(FIGS. 85 c-85 e). The slotted guide tube 925 also may be formed bysequentially extruding a dual lumen catheter shaft 930, forming a slotin a slot forming operation, and removing a proximal and/or distalportion of the guide tube 925 in an optional material removing operationto set the length of the guide tube. In the slot forming operation, alongitudinal cut can be formed along at least a portion of the length ofthe guide tube. The lower edge 945 then is pressed down and inwardlybelow the upper edge 940. The upper edge 940 can simultaneously or laterby pressed downwardly and over the lower edge. The edges then can be setin place relative to each other by, for example, applying heat.

Referring to FIGS. 86 a-86 h, a rapid exchange catheter 950 includes aslot 955 along its length. The slot 955 includes one or two flexibleedges 930 that meet along a longitudinal perforation or weakened section935 (FIG. 86 c, 86 d, 86 f). The flexible edges 930 can be joined andthe section 935 can be perforated such that a guide wire can be pulledout of a guide wire channel 960 by rupturing the longitudinalperforations 935 (FIG. 86 g). In another implementation, the flexibleedges 930 can be joined and the section 935 can be scored such that theweakened section 935 can be longitudinally torn by pulling the guidewire out of the guide wire channel 830 (FIG. 86 g). The perforation orweakened section 935 can be formed by merely scoring or perforatingalong the length, for example, by extruding such that the upper wall ofthe weakened section is extruded relatively thin. In anotherimplementation, the perforation or weakened section can be formed byinitially removing an outer wall thickness and then perforating orscoring the thinned wall. In either manner, the weakened section 935will be more easily opened such that the guide wire can be removed fromthe channel 830.

The slot 955 may extend distally from the balloon a short distance, allthe way to the distal tip, or not at all. The slot 955 may extendproximally from the balloon 810 a short distance, all the way to aposition adjacent to the hub, or a position in between. As such, becausethe guide wire can be removed from the channel 830 at any point alongits length, the length of the slot can be any length and not adverselyaffect the ability of the physician to remove the guide wire. Thus, thelength of the slot 955 relative to the remainder of the channel 830 canbe tailored to beneficially affect other characteristics of the catheter950 as needed by, for example, placing a mandril in the remainder of thechannel 830.

The slot 955 may be formed in a separately extruded tube, perforated orweakened, and then firmly attached to the catheter. In anotherimplementation, the catheter is extruded as a dual lumen catheter andthen the perforation or weakening is performed.

Referring to FIGS. 87 a-87 j, a rapid exchange catheter 975 includes oneor more guide sections 980. The guide sections 980 include alongitudinal channel 830 sized to receive a guide wire. The guidesections can include a longitudinal slot as described in the variousconfigurations above (FIGS. 87 h, 87 i, 87 j). The guide sections canhave tapered leading and trailing edges 990 that provide for atraumaticinsertion and removal of the catheter 975. The guide sections 980 can beformed as a separately extruded tube that then is firmly attached to thecatheter or extruded integrally with the catheter 975 as a dual lumencatheter shaft with a subsequent material removal operation.

Although the catheters described above are illustrated to have only asingle chamber balloon, a multiple chamber balloon (i.e., two balloonchambers, three balloon chamber, four balloon chambers, or more) alsocan be used. As illustrated in FIGS. 88 and 89 a, a multi-chamberdilation balloon 1000 is formed to extend axially along a distal endregion of a catheter. The balloon 1000 has several longitudinalcompartments 1005, 1010, 1020, and 1025 all angularly adjacent to oneanother and cooperating to surround the catheter as seen in FIG. 88. Thecompartments 1005, 1010, 1020, and 1025 have radially outward wallsegments 1030, 1035, 1040, and 1045, respectively, which cooperate toprovide a continuous outer wall 1050 for the balloon 1000 and areadapted to engage a tissue wall segment of a vessel, such as an artery,over substantially the balloon's entire surface area. The balloon alsohas interior walls 1050, 1055, 1060, and 1065, respectively, whichangularly divide the balloon 1000 into the plurality of the dilatationcompartments 1005, 1010, 1020, and 1025 adjacent to one another andarranged angularly about the catheter tubing or shaft 1070. As seen inFIG. 88, each compartment extends approximately 90° angularly orcircumferentially about the catheter tubing or shaft 1070. Each of thecompartments is fluid tight and in fluid isolation from the othercompartments. Thus, each compartment can be inflated to a differentpressure to provide an eccentric cross-sectional profile. As one skilledin the art can appreciate, the balloon 1000 can be constructed to haveany desired number of dilatation compartments and the balloon may haveany range of accepted inflated diameters, such as an outer diameter of 3mm when it is inflated about the catheter shaft. Each compartment 1005,1010, 1020, and 1025 has a separate inflation lumen 1006, 1011, 1021,and 1026 for individually controlling the inflation of that lumen. Theballoon material may be made of a compliant material such aspolyethylene or polyurethane or other similar suitable material, etc.Alternatively, it may be an inextensible material such as nylon, PET andpolyamide, or other similar suitable material, etc.

The interior balloon walls are formed by overlapping two layers of theballoon material. The four-compartment balloon 1000 is constructed byusing a clip 1075 with four prongs 1080 that are used to draw or pressportions of an inflated balloon against the outside surface of catheter1070 as shown in FIG. 89 a. The configuration then is set using methodsknown in the art, such as applying heat. Another method of constructionis to create one balloon with interior walls of single thickness. Forexample, the balloon can be blown inside of a glass mold with thedesired configuration. Moreover, the balloon 1000 can have any of theguide wire/perfusion configurations describe above. For example, thecatheter can have a slotted channel that passes through the shaft and ora slotted channel that passes over the shaft.

The balloon may have a tapered geometry and/or two different diameters.One advantage of a tapered and/or multiple diameter balloon is that alarger section can function as a guide, reference, or stop whendeploying a stent in the ostium to treat ostial lesions. Because of itssize, it is unlikely that the larger diameter can be inserted into thecoronary artery to allow accurate stent placement. A major complicationthat can occur when stenting the ostium is that of a section of thestent being deployed partially outside of the ostium and partially inthe aorta. In this manner, the balloon can be partially inflated suchthat the larger diameter proximal section of the balloon is inflated andwhen pressed up against the coronary artery, the inflated balloonprevents that portion of the balloon from entering the coronary artery.Referring to FIGS. 89 b-89 e, if a stent 1081 is placed on a smallerdiameter distal portion 1082 of a balloon 1083, only that portion of theballoon, along with the stent, will be inserted into a coronary artery1084. A larger diameter portion 1085 of the balloon 1083 will not enterthe coronary artery 1084 when the larger diameter portion is at leastpartially inflated. Then, by inflating the balloon 1083 completely, thesmaller diameter distal portion 1082 of the balloon will be inflatedsufficiently to deploy the stent 1081 in the coronary artery without anyof the stent extending into the aorta. In an alternative method, theballoon can have a constant diameter and the stent again placed on thedistal portion of the balloon. Then, by partially inflating the balloonto a pressure sufficient to expand the portion of the balloon aroundwhich the stent has not been placed or crimped but not enough to deploythe stent, a larger diameter portion of the balloon will be created.When the catheter is advanced into the coronary artery, the expandedportion of the balloon will be unable to enter the coronary artery ifthe balloon has been sized properly. Thus, the stent will be entirelywithin the coronary artery and not extend into the aorta. The ballooncan then be completely inflated and the stent deployed. Althoughdescribed above with respect to one particular anatomical position, thistechnique can be implemented in other anatomical locations within thebody.

The balloon 1000 and rapid exchange catheters described above can beused in balloon angioplasty, stent deployment and other procedures. Forexample, the inflatable balloon catheter 1000 having four dilatationcompartments 1005, 1010, 1020, and 1025 can be inserted in a vesseluntil it reaches the obstructed area. Radiopaque markers can be placedon the catheter shaft under the balloon 1000 to assist the physician inpositioning the balloon adjacent an obstruction. The multiplecompartments of the balloon are then inflated to contact theobstruction.

The balloon catheter also may additionally be used in stent deployment.A plastically expandable stent 1085 that substantially surrounds theballoon 1000 of a catheter, in any of the embodiments describe above,may have the four dilatation compartments 1005, 1010, 1020, and 1025.Once the balloon 1000 and the stent are located at the appropriatelocation within the vessel and adjacent an obstruction 1090, the ballooncompartments are inflated to deform the stent into contact with theobstruction. The physician is able to control stent deployment byadjusting the inflation of the balloon dilatation compartments asnecessary. Greater inflation may be required for dilatation compartments1015 and 1020 than compartments 1005 and 1010. Thus, compartments 1015and 1020 can be monitored so that over inflation (that could causevessel damage) in the obstructed area 1090 would be avoided.Furthermore, by viewing the pressure between the artery wall and balloonwith regard to the balloon inflation pressure, the physician candetermine that the stent 1085 is fully deployed.

For multi-balloon versions of the catheter, the individual balloons maybe tailored or designed for specific purposes. For example, the balloonintended to open an occlusion, may be different than the balloon that isintended to deploy a stent or a balloon with therapeutic infusionfeatures. Examples of different version are found in Houser (U.S. Pat.No. 5,865,801), which is incorporated herein in its entirety byreference.

FIGS. 91 a-91 g and FIGS. 92 a-92 f are examples of implementations ofthe multi-compartment balloon 1000 mounted on the catheters describeabove. For example, FIGS. 91 a-91 g illustrate a balloon catheter 1100having one or more slotted guide wire/perfusion channels 1105, a markerband 1110, and a balloon with one or more compartments 1115, 1120, 1125,and 1130.

FIGS. 92 a-92 f are side and cross-sectional views of a second ballooncatheter 1150 having the multi-compartment balloon 1000 mounted on acatheter as described above and includes one or more slotted guidewire/perfusion channels 1105, a marker band 1110, and a balloon with oneor more compartments 1115, 1120, 1125, and 1130.

Referring to FIGS. 93 a-93 f, a catheter 1200 can be fabricated with apeelable guide wire opening 1205. In this configuration, the cathetershaft is extruded with an inflation lumen 825, a guide wire lumen 830,and a peelable lumen 1210 that is accessed by pulling a wire 1215 alonga portion of the length of the catheter. As best seen in FIG. 93 e, thecatheter shaft is extruded with the peelable lumen containing a wire ormandril 1220. A thin catheter wall is between the wire 1220 and theouter diameter of the catheter. A thin wall also is between the wire1220 and the guide wire lumen 830. To remove the guide wire 135, thephysician nicks the catheter shaft with, for example, a scalpel or pairof scissors, to expose the wire 1220 and bends the shaft to more easilyaccess the wire. The wire 1220 then can be pulled longitudinally alongthe length of the catheter shaft or along a portion of the length of thecatheter shaft to create the opening 1205 to the lumen 1210 (FIG. 93 b).The physician can use, for example, a pair of tweezers or hemostats topull a loop of wire from the lumen 1210 to initiate the opening. Oncethe opening 1210 is made, the physician can slightly bend the catheterto manipulate the guide wire 135 through the wall between the guide wirelumen 830 and the lumen 1210, and out the opening 1205 (FIG. 93 c).

The peelable configuration has been described with reference to acatheter. However, this configuration also can be applied to a methodand design of other medical products, such as a vascular introducer,sheath, or deployment device for deploying a medical device. The wirecan be configured as a string, wire, multi-filament wire, polymer cord,polymer strand, multiple polymer strands, or any similar element.

Referring to FIGS. 94 a-94 d, the catheters described above can be madeto have a reduced diameter cross-sectional profile by incorporatingthose features on a catheter 1225 having a collapsible ballooninflation/deflation lumen 825. For example, the collapsibleinflation/deflation lumen 825 can extend the full length of the catheteror be confined to the distal section only. The collapsible lumen isconfigured to collapse onto itself when a negative pressure or vacuum isapplied. During insertion, this is beneficial to further reduce thecrossing profile. This characteristic may be accomplished by making thelumen walls thinner at the desired area(s), or other method, while stillbeing able to contain the internal pressure when the balloon isinflated. This also may be accomplished by making the catheter shaftfrom two materials in a co-extrusion. A first material 1230 surroundsthe guide wire lumen and a second material 1235 surrounds thecollapsible lumen. The first material is more rigid than the secondmaterial and therefore is less likely to collapse upon itself whenvacuum is applied. The second material is more flexible and collapses ata lower pressure than does the second material. The configurations ofFIGS. 94 a and 94 b also can be fabricated with the materials 1230 and1235.

FIGS. 95 a-95 s and 96 a-96 s are examples of more specificimplementations of the techniques and features described above andinclude more specific detail to enable one of skill in the art inimplementing the techniques and features described above. Theseimplementations are merely representative examples of twoimplementations and, as such, the specific values provided below areexpected to differ significantly and/or insignificantly in otherimplementations.

In particular, referring to FIGS. 95 a-95 s, a catheter 1300 includes ahub 1305, a shaft 1310, an inflatable balloon 1315, and a distal tip1320. A guide wire 135 extends from the distal tip. As illustrated inFIG. 95 b, at section D-D the shaft 1310 has an inner diameter of 0.020inches and an outer diameter of 0.036 inches and a single lumen 1325. Asillustrated at FIG. 95 c, at section E-E, the shaft 1310 has an outerdiameter of 0.039 inches and includes the lumen 1325, which is used toinflate the balloon 1315, and a channel 1330 that is used to carry orcontain a guide wire. FIG. 95 d is a cross-sectional view of the guidewire, shaft and balloon at section F-F and illustrates the balloon 1315having two edges 1335 in contact above an opening 1340 into the channel1330. A 0.014 inch guide wire 135 is shown being in the channel. Theopening 1340 of FIGS. 95 c and 95 d is wide enough to receive and removethe guide wire 135. The opening also is wide enough to include the wallsof the balloon, which is bonded to the catheter inside the channel 1330.An inflation opening 1345 is shown passing between the inflation lumen1325 and the interior of the balloon 1315. The only openings into theinterior of the balloon are the inflation opening(s). The inflationopening is shown as being 0.020 inches wide at section F-F and thecatheter shaft passing through the balloon is shown as having a 0.039inch diameter. FIG. 95 e is a cross-section view of the guide wire,shaft and balloon at section G-G and illustrates the guide wire passingthrough the guide wire channel 1330. FIG. 95 f is a cross-sectional viewof the guide wire and shaft at the distal tip 1320. Again, the guidewire is within a channel 1330 having an opening 1340 that is configuredto receive a guide wire and allow the guide wire to be easily removedfrom the channel.

The catheter 1300 of FIGS. 95 a-95 s is fabricated with the balloon 1315being bonded within the channel 1330 and the ends of the balloon beingbonded to the shaft, as best illustrated in FIGS. 95 i and 95 k. Theballoon is placed around the shaft (i.e., insert the shaft into thechannel through the balloon) and the balloon ends and a longitudinallength of the balloon are bonded to the portions of the shaft and withinthe guide wire channel, respectively. The edges of the balloon formed atthe channel then will meet when the balloon is inflated.

FIG. 95 g illustrates the length of the catheter 1300 beingapproximately 140 cm from the hub to the distal tip of the catheter1300. FIG. 95 i illustrates a close-up view of the balloon and shows howthe guide wire is underneath the two joined edges 1335 of the balloon.FIG. 95 i also illustrates the tapered end of the distal end of theballoon, which has a taper length of approximately 0.097 inches (2.5mm). FIG. 95 h illustrates that the proximal shaft may have a diameterof approximately 0.036 inches and the distal shaft (although proximal tothe balloon) may have a diameter of approximately 0.038-0.039 incheswith a transition area 1350 between the distal and proximal shaft. Thedistal shaft may be approximately 20 cm, and the entry of the guide wireinto the guide wire channel may be approximately 15 cm from the distaltip of the catheter.

FIGS. 95 j and 95 k illustrate the balloon 1315 and an optional markerband 1355 placed under the balloon around the shaft. The marker band canbe used to restrain the guide wire or direct its passage. FIGS. 95 l, 95m, 95 n, and 95 o provide additional details about the balloon that arespecific to this particular implementation. In this implementation, theballoon has an outer diameter of approximately 0.118 inches (3 mm), awall thickness of 0.003 inches, a taper width of 0.006 inches betweenthe balloon edges 1335, and a length of approximately 20 cm.

FIGS. 95 p-s illustrate additional details about the shaft. For example,the inflation lumen is shown as having a width of approximately 0.028inches, a center height of approximately 0.006 inches, a wall thicknessaround the inflation lumen of approximately 0.005 inches, an opening1340 into the guide wire channel of approximately 0.012 inches, edges ofapproximately 0.005 inches in thickness, and a guide wire channeldiameter of approximately 0.020 inches.

FIGS. 96 a-96 s illustrate a catheter 1400 that is similar in manyrespect to the catheter 1300 describe above. However, the catheter 1400includes a narrower opening 1405 into a guide wire channel 1410. Forexample, the narrower opening 1405 may be approximately 0.006 inches(instead of the approximately 0.012 inches of the catheter 1300) becausethe catheter has the balloon bonded around the outer circumference ofthe shaft rather than in the guide wire channel, as is the manner withcatheter 1300. The balloon is wrapped around the catheter shaft untilthe balloon edges are adjacent and then the balloon is bonded to theshaft. As such, the two edges of the balloon will contact each otherupon inflation.

In general, the catheters described above have a proximal adapter thatcan be configured as, for example, a single Luer fitting for a singlechamber or compartment balloon inflation, or multiple fittings formultiple balloon chamber, compartment, or segment inflation. Themultiple balloon chamber or segment inflation can be individual and/orsimultaneous. The multiple balloon chambers or segments may or may notbe in fluid communication with each other.

The proximal shaft can be bonded together with the distal shaft using aTeflon coated mandrel that is inserted into the inflation lumen andheated to join both tubing sections together. FEP or PTFE tubing can beplaced on the outside of the tubing to maintain the OD size during thejoining process and then removed. The proximal shaft also can include amoveable/replaceable reinforcing or shaping member, as described above.The member may or may not continue through the distal section of thecatheter and may be inserted into a dedicated lumen, or may use theinflation/deflation lumen during insertion. The distal shaft also mayinclude the same or a different moveable/replaceable reinforcing memberas described above. The member may be inserted into a dedicated lumen,or the inflation/deflation lumen during insertion and removed for theinflation.

The guide wire can be contained as described above along the entirecatheter length; in the distal section only; in the proximal sectiononly; through, over, or parallel to the balloon; in the distal tip only;on top of the tip; inside the tip; inside the tip in between or under amarker band; and/or with an eyelet or coil configuration. Thecontainment of the guide wire can also serve as a perfusion lumen andcan be a channel having incomplete circumferential coverage withinterior geometry matching the radius of the guide wire; a channel withone or more guide wire “hold downs” (i.e., partial coverage in a mannerthat is similar to catheter packaging trays); a limited length lumen orchannel that is under and through the balloon but on top of cathetershaft; constrained in between balloon segments or detent(s), on top ofthe balloon, or on top of the catheter shaft; and/or on top of, orthrough the distal tip (i.e., at a position forward of the balloon).

The balloon can be a single chamber balloon with non circumferentialgeometry (i.e., incomplete circle, cross section void) in which the noncircumferential geometry section is partial of the balloon height (i.e.,above the shaft) or in contact and bonded together with the top of theshaft. When a grooved balloon is used with incomplete circumferentialcross section geometry, the seam where the ends of the balloon cometogether may be longitudinal, or other, such as spiral, and can haveinterlocking end geometries (“S” or other profile).

The balloon also can be a multi-chamber or compartment balloon asdescribed in Houser, U.S. Pat. No. 5,865,801, which is incorporatedherein by reference in its entirety. When multiple grooved balloons areused (i.e., with an incomplete circumferential cross section geometry),the seam where the ends of the balloon come together may belongitudinal, or other, and can have interlocking end geometries (“S” orother profile).

The balloon inflation can be accomplished in a number of ways. Forexample, the non-circumferential geometry balloon may havecircumferential interior vessel contact when inflated. Inflation of theballoon in a confined space will cause the radial ends of the balloon tocome together, in particular when the balloon is made, partially orcompletely, from a compliant material, such as the materials describedin Houser, U.S. Pat. No. 5,865,801.

The balloon is bonded to the catheter shaft by using a variety ofmethods, as described above, and includes the use of adhesives,solvents, heat, a combination of these, or other any other suitablemethod as known to those in the art.

The bonding of the balloon to the catheter shaft may further beconfigured in the traditional method, namely, the balloon shouldersbeing bonded to the catheter shaft. The balloon also may be bonded tothe top with the balloon wall bonded inside the guide wire channel(maintaining channel geometry). The outside of the top of balloon may bebonded to the bottom of the shaft, with the balloon shoulders beingmodified (i.e., sections removed so that there are not two layers ofballoon material where the shoulders are bonded to the shaft). Theballoon also may have a hole that is positioned and secured to alignwith the inflation/deflation port on the catheter shaft. Thelongitudinal edges of the balloon may be designed to expand and come incontact closest to the shaft initially, but with increasing internalballoon pressure, the contact of the balloon edges continues in anoutward direction from the shaft to the outer surface of the balloon.

The balloon may be a single or dual longitudinally spaced balloons thatare inflatable independently, or simultaneously. The balloon geometrymay be different between balloons and non concentric, noncircumferential balloon geometries may be used. The balloon may haveopenings to bond onto the shaft at the proximal and distal ends. Theballoon also may also have a longitudinal edge, seam, opening, orcross-sectional void, to allow longitudinal bonding of the balloondirectly to the catheter shaft, and also to create a void for the guidewire channel. The balloon strength may be increased by exposing theballoon material to radiation which causes cross-linking of the polymerchain.

The balloon also can be processed to impart a smaller cross section“memory” profile, after the balloon (and or balloon chambers orsegments) has been inflated, deflated, and is ready to be withdrawn fromthe body (causing the balloon “wings” to be closer to the catheter shaftafter deflation making it less likely to dislodge emboli or cause otherdeleterious effects during withdrawal of the catheter from the body).The process may include irradiation to cross-link, or heating to anneal,the balloon material while in a constrained configuration. Certainballoon materials and or compound additives, such as, for example,ProRad, may be used to impart this characteristic.

The balloon also may be designed to have sections that expand atdifferent rates and/or lengths during inflation. This characteristic maybe realized by several methods, such as by thinning the balloon wall inthe areas to allow for more expansion, and/or a special extrusion withdifferent materials at different areas around the circumference of theballoon tubing (e.g., extruding more elastic material in the areas thatare desired to expand more). This method also may produce a balloon withasymmetric inflation utility.

The balloon also may have a reduced diameter profile in the area justunder the stent, such as the sides, to reduce the crossing profile aswell as to “nest” the ends of the stent, which reduces the potential forthe stent end to abrade the inside of the vessel during stentadvancement in the vessel.

A coil or other mandrel may be inserted into the inflation lumen duringthe inserting into the vascular system, to provide additionalpushability. The coil or other mandrel may or may not be removed priorto inflating the balloon.

The distal tip may be heat formed to taper to seal theinflation/deflation lumen and provide a tapered transition between theguide wire and tip of catheter

The catheter can be used in stent deployment, drug delivery, therapeuticinfusion, and/or other diagnostic, therapeutic, preventative proceduresor any combination of these or other suitable procedure. For example,the catheter can be used for therapeutic infusion by including ports or“weeping” through on the balloon, recessed region in the balloon forpooling of therapeutics for prolonged exposure, as described in greaterdetail in Houser (U.S. Pat. No. 5,865,801). The catheter also can beconfigured to have an infusion port in between a pair of lumens. Theinfusion port may be in fluid communication with the proximal end of thecatheter using a Luer fitting or other suitable fitting. The infusionport also can be implemented using a separate, full catheter lengthlumen.

The catheter also can be configured to include one or more lumens andport(s) that exit the catheter wall, are located proximal to and/ordistal to the balloon, or in the case of multiple balloons, in-betweenmultiple balloons. This feature may be used for therapeutic ordiagnostic fluid suction and/or infusion, or may used for otherpurposes, such as to insert a device or other object.

The balloon may be formed as described, for example, in Anderson (U.S.Pat. No. 6,007,517), which is incorporated herein by reference in itsentirety. The balloon may be formed with flow channels for perfusion orguide wire passages passing through it. The channels or passages can beformed by molding and/or extrusion techniques. In one method, a modifiedmodeling process, prior to the molding process, both the proximal anddistal ends of the balloon are affixed to the catheter shaft. Theballoon has excess material about the sites where one or more channelsare to be formed. The excess material corresponds to the surface(s) onthe interior to the balloon and therefore will be sufficient to permitformation of inner channels or passages. If the channel or passagematerial should be thicker than typical, the manufacturer can usethicker material in this region where excess material is desired. Thiscan be accomplished in several ways. In one aspect, prior to bonding tothe shaft, the balloon material is extended with thickened walls in theregions where a channel is to be formed. The quantities of excessballoon material and proper thickness can be determined in a given caseby routine experimentation. Upon molding, the thicker regions form thechannels. Alternatively, one can layer standard longitudinal sections ofballoon material in those regions where thickening is required usingbonding techniques and then mold the balloon. The bonded layer not onlythickens the regions needed to form the channels but functions as ascaffold. Conventional adhesives also can be used to bond the extrudedballoon to the shaft. The layers also can be conventionally heat-sealed.The channel walls also can includes materials other than balloonmaterials that are adjoined to the balloon to form the channels. Inaddition, the channel walls can be treated to increase strength.

During manufacturing, one or more cylindrical members may be placedwithin a balloon mold in the position of the one or more desiredchannel(s). The members may be pre-mounted to the mold. When the balloonis inflated within the mold, the excess balloon material envelopes thecylindrical members. During or after the molding process, the contiguousballoon material is conventionally heat sealed to form the channel(s) oris otherwise sealed using, for example, adhesives. For example, once theballoon molding is completed, the mold is separated, the cylindricalmembers used to support the flow channels during molding are removed,and the initially excess balloon material is bonded together using thetechniques describe above to complete its circumference. That excessmaterial will have formed channel(s) and includes the outermost portionof the channels. It is also possible to use one or more movablecylindrical members that are moved toward each other during the moldingprocess to facilitate achievement of the channels.

In another manufacturing method, the balloon and its one or morechannels are extruded using conventional plastic extrusion technology.The one or more interior channels are achieved by extrusion of one ormore cylinders or mandrils or wires having walls of a desired thicknesswithin the larger cylinder that is the balloon. The inner channel may beextruded at the same time as the exterior balloon in a single process.The channel(s) also may be separately extruded and then added to theinterior of the larger, exterior balloon at the time of assembly bysealing using, for example, adhesives or by heat sealing and cuttingaway the openings to the channels.

Referring to FIGS. 97 a-97 e, a catheter 1500 includes a hub 1505, ashaft 1510, one or more balloons 1515, and one or more slotted guidewire tubes 1520 through which guide wires, embolic devices, or othertherapeutic or diagnostic devices can be passed. A central lumen 1525 ofthe shaft 1510 can include a pair of lumens 1530 and 1535 for, e.g.,inflating the balloon(s) 1515, passing additional devices, or infusingtherapeutic or diagnostic agents. The slotted guide wire tubes 1520include a channel 1540 into which the guide wire can be slidablyinserted and/or press through the slot into the channel 1540. Although asingle slotted guide wire tube 1520 is illustrated, additional guidewire tubes 1520 can be placed along the entire length, part of thelength, or at any position along the length of the catheter. Theballoons 1515 can be separately inflated or simultaneously inflated andcan be configured as a pair of balloons (FIG. 97 b), a single balloonthat encircles a portion of the circumference of the catheter 1500 (FIG.97 c); four balloons (FIG. 97 d), or three balloons (FIG. 97 d).Although a catheter 1500 is illustrated with one to four balloons, moreballoons can be placed around the circumference of the catheter.

The potential benefits of these balloon designs include the ability toposition a non-balloon section or a reduced balloon section over acalcified lesion to reduce or eliminate direct pressure at that site,which is believed to be useful in preventing damage to the vessel. Thedual balloon configuration (FIG. 97 b) has a generally hour-glass shapedballoon configuration that allows radial expansion in a single plane orreduced circumferential distance, rather than the completelycircumferential expansion as the typical balloon catheter is inflated.

Referring to FIGS. 98 a-98 d, a balloon catheter 1550 is configured toprovide a side port 1555 through a balloon 1560 for advancing a device,such as a guide wire 1565. In this manner, guide wires can be placed foradvancing a bifurcated stent into a main vessel and a side branch ofthat main vessel. In contrast to the balloon catheter 1500, the ballooncatheter 1550 is formed in the balloon forming process with a fold 1570along its length. The catheter 1550 includes a shaft 1575 having atleast one lumen 1580 and a pair of guide wire channels 1585, 1590 thatrun along at least a portion of the length of the shaft. For example,either or both of the channels 1585, 1590 can pass along the cathetershaft 1575 below the balloon 1560 for the entire length of the balloonor a portion of the length of the balloon, as illustrated in FIG. 98 a.The fold 1570 can be positioned above one of the channels 1590 and aradial channel 1595 formed in the fold between the channel 1590 and theside port 1555. As described below, the radial channel 1595 can beformed, for example, during the balloon formation process by inserting apin between the folds. The radial channel 1595 may be an indention inthe balloon material that forms the channel when the opposing sides ofthe fold are apposed upon inflation. The guide wire channel 1590 canterminate or have an opening that is contiguous with the radial channel1595. In this manner, a guide wire in the guide wire channel 1590 can beadvanced forward into the vessel in which the catheter 1550 is placed byleaving the balloon deflated or by inflating the balloon and advancingthe guide wire into the radial channel 1595, through the side port 1555,and into a branch of the vessel from the main vessel. Or, as describedbelow, a diagnostic or therapeutic device can be passed through theradial channel 1595 into the side wall of the vessel surrounding thecatheter.

Referring also to FIGS. 98 e-98 h, in one implementation, the diagnosticdevice can be a hollow-tipped guide wire 1600 that can be inserted intotissue and/or plaque 1605 to obtain a biopsy or plaque sample from avessel 1610. The guide wire tip 1615 is hollow or includes an opening1620 to received tissue or plaque 1605. The tip 1615 may be sharpened tofacilitate insertion into tissue or plaque 1605. The length of a hollowsection 1625 is long enough to provide a sufficient quantity of materialto analyze. Although the device is described as being a hollow-tippedguide wire, it also may be a tube, probe, or other similar device thatcan be guided along the catheter, through a portion of an inflatedballoon (or, alternatively a catheter without a balloon), and bedirected through the vasculature to a desired location along the vesselwall. For example, a diagnostic instrument such as an ultrasonictransducer or device for visualizing or ablating, a tissuedensity-measuring device, an oxygen-sensing probe, a temperature-sensingprobe, or other suitable type of probe may be used to analyze thecharacteristics of the plaque.

The hollow tipped guide wire or other suitable device is used to access,capture, and retrieve a sample of the lesion (including plaque or othertype of occlusion) for better diagnosis and to choose the best mode oftreatment. For example, the retrieved tissue, lesion, or plaque may beanalyzed to determine its physical and chemical composition before thephysician decides the most appropriate treatment method for thatparticular site. For therapeutic purposes, a special hollow guide wireor infusion device may be used to infuse a therapeutic material, such asa pharmacological or gene-therapy based agent at, in or near the plaque,occlusion or vessel wall. The infused or applied material may includematerials that would bind, reinforce, seal or stabilize the occlusion toprevent or make the vulnerable plaque less likely to rupture. Examplesof the general classes of these materials include an adhesive and/or apharmacological material. The infused material may be a liquid thatbecomes a solid or gel upon placement and/or activation.

The guide wire 1600 can be used in the diagnosis and treatment ofvulnerable plaque by obtaining a sample of plaque and identifyingcharacteristics of vulnerable plaque: Some of the diagnostic methodsinclude temperature measurement (by means of one or more of athermocouple, thermistor, fluorescing means or other temperature sensingmeans), density measurement, oxygen content measurement, compositionanalysis, shape or size characteristics, location within the lesion,and/or physical strength.

In this implementation, a first guide wire 1630 may be used to directthe catheter to the desired location and a second guide wire 1600 may bethe hollow guide wire for tissue or plaque access and retrieval. Whenthe catheter is used to access and retrieve a lesion sample, the balloon1560 may be inflated to a lower pressure than would be used for atherapeutic dilatation so that the lesion remains stable during theprocess of accessing and removing the sample. The balloon can remaininflated, if necessary, to keep it stable during the time required toanalyze the sample to determine it composition and the best treatmentfor the particular lesion. For periods of extended balloon inflation, aperfusion feature (e.g., a perfusion lumen in or on catheter shaft oropenings through the tubing wall placed proximal and distal to theballoon) may be included in the catheter design.

Referring to FIGS. 99 a-99 e, a catheter 1650 can be configured with aguide wire channel 1655 that is within a catheter shaft 1660, a balloon1665 that includes a radially extending channel 1670 that terminates ata side port 1675. The radially extending channel 1670 is formed in afold 1680 in the balloon 1665. In contrast to the balloon catheter 1550of FIGS. 98 a-98 d, the balloon 1665 and the fold 1680 extend into theguide wire channel 1655. The guide wire channel 1655 can extend theentire length of the balloon 1665, as illustrated in FIGS. 99 a-99 d, oronly a portion of the length of the balloon. For example, the ballooncan extend only to the radially extending channel 1670 such that a guidewire or other device that is inserted into the guide wire channel 1655will pass into the radially extending channel and can be advanced into abranch vessel or into the vessel wall or plaque, as described above.

The fold 1680 and radially extending channel 1670 can be formed byplacing a cylindrical member, such as a pin 1690 (FIG. 99 e) in a moldand forming the balloon around the pin. The pin 1690 include a firstsection 1692 and a second section 1694. The first section 1692 and thesecond section 1694 are joined at an angle A. The first section 1692 isplaced within the guide wire channel 1655 and the second section 1694then corresponds to the radially extending channel 1670. The angle A canbe set at any angle between slightly greater than 0° and slightly lessthan 180°, although the most typical angle will be an angle betweenapproximately 90° and approximately 150°.

Although only one cylindrical member or pin can be used in forming theradially extending channel, one or more cylindrical members or pins canplaced within the balloon mold in the position of the one or moredesired channels. When inflating the balloon within the mold, theballoon material envelopes the one or more cylindrical members to formone or more radially extending channels. The members may be pre-attachedto the mold or may be a separate piece or pieces. These and otherballoon forming methods known to those of skill in the art are disclosedin Houser (U.S. Pat. No. 5,865,801) and Anderson (U.S. Pat. No.6,007,517), both of which are incorporated herein by reference.

Another version of the catheter design may be implemented without aballoon. This implementation may be used as a carrier for insertion ofmultiple guide wires, catheters, and/or other devices, such as leads, atvarious locations within the cardiovascular system, particularly themain and branching coronary arteries. Once the guide wires have beeninserted into the desired vessels (e.g., main vessel and side branch)the guide wire carrier catheter is withdrawn. The proximal ends of theguide wires may be temporarily or permanently marked with the specificanatomic location of each guide wire. Therapeutic, diagnostic or othermedical devices (including other catheters) may then be guided to theappropriate anatomic location by the previously inserted guide wires.

The catheters described herein optionally can be configured to provideelectroporation during therapeutic infusion. In this mode, the cathetersprovide the ability to actively stimulate tissue to facilitateintracellular application of the therapeutic solutions. For example, asection of the balloon or catheter body may include a component orcoating that can function as an electrode to deliver high voltageelectrical pulses into adjacent tissue to cause electroporation oftissue within the desired region, for greater absorption of thetherapeutic fluid into the tissue.

The catheters described herein also optionally can be configured toinclude a piezoelectric film on the balloon for inducement of cavitation(e.g., during therapeutic infusion), an ultrasonic transducer to providefor visualization, ultrasonic ablation, electroporation, and/or pressuresensing devices. The catheters also can optionally include heatingcapabilities without or without temperature sensing or control usingdirect resistive element or ohmic tissue methods to treat tissue,deliver or deploy a shape memory stent or other shape memory device. Theheating capabilities can be provided using one or more heating means,such as a thin film heating element, a resistive wire or strip (e.g.,for resistive element heating), a conductive wire or strip (e.g., forohmic tissue heating), or an ultrasonic transducer. The heating meanscan be positioned on the catheter, on or inside the balloon, or as aseparate device positioned within or adjacent to the catheter. Many ofthese features and capabilities are described in Houser (U.S. Pat. No.5,865,801).

While several particular forms of the invention have been illustratedand described, it will be apparent that various modifications andcombinations of the invention detailed in the text and drawings can bemade without departing from the spirit and scope of the invention. Forexample, references to materials of construction, methods ofconstruction, specific dimensions, shapes, utilities or applications arealso not intended to be limiting in any manner and other materials anddimensions could be substituted and remain within the spirit and scopeof the invention. Finally, it is contemplated that any single feature orany combination of optional features of the inventive variationsdescribed herein may be specifically excluded from the claimed inventionand be so described as a negative invention. Accordingly, it is notintended that the invention be limited, except as by the appendedclaims.

1.-37. (canceled)
 38. A catheter configured to be inserted into a vesselwithin a mammalian body, the catheter comprising: a tubular body havingan exterior surface, a first end and a second end that define a lengthbetween the first end and the second end, and a central lumen extendingalong the tubular body at least for a portion of the length of thetubular body; and at least one channel extending along the exteriorsurface of the tubular body at least for a portion of the length of thetubular body, the channel including a first opening, a second opening,and the channel passing between the first opening and the secondopening, wherein the channel includes a slot opening into the channelsuch that a tubular member can be passed between the channel and theexterior surface of the tubular body, wherein the slot extends from thefirst opening to the second opening and includes a pair of edges,wherein the tubular body has a circumference that defines a non-circularshape.
 39. The catheter of claim 38, further comprising a balloonextending around the tubular body proximal of the second end of thetubular body.
 40. The catheter of claim 39, wherein at least a portionof the balloon is in contact with the exterior surface of the tubularbody and the channel.
 41. The catheter of claim 39, wherein the balloonextends into the channel for at least a portion of the length of thechannel.
 42. The catheter of claim 41, wherein the balloon furtherincludes a first surface extending from the channel and a second surfaceextending from the channel.
 43. The catheter of claim 42, wherein eachof the first surface and the second surface include a radially extendingchannel passing between the channel and an opening on an outer surfaceof the balloon.
 44. The catheter of claim 40, further comprising a bandencircling at least a portion of a circumference of the tubular bodyunder the balloon.
 45. The catheter of claim 39, wherein the ballooncomprises at least two discrete diameters.
 46. The catheter of claim 39,wherein the balloon comprises a diameter that is tapered along a lengthof the balloon.
 47. The catheter of claim 39, wherein the balloon is astent delivery balloon.
 48. The catheter of claim 38, wherein the edgesof the slot overlap.
 49. The catheter of claim 38, wherein the edges ofthe slot are aligned and in contact along at least a portion of thelength of the edges without being connected.
 50. The catheter of claim38, wherein the edges are aligned and spaced apart from one another. 51.The catheter of claim 38, wherein the non-circular shape comprises agenerally oval shape.
 52. The catheter of claim 38, wherein thenon-circular shape comprises a height that is greater than a width. 53.The catheter of claim 38, wherein the tubular body and channel areintegrally formed.
 54. The catheter of claim 53, wherein the slotopening into the channel is formed in a secondary operation.
 55. Thecatheter of claim 53, wherein integrally forming the tubular body andthe channel comprises extruding the tubular body and channel together.56. The catheter of claim 38, wherein at least a portion of the centrallumen of the tubular body and the channel run parallel to each otherwithin an oval-shaped segment of the catheter.
 57. The catheter of claim38, further comprising a second channel extending longitudinally alongthe tubular body at least for a portion of the length of the tubularbody.
 58. The catheter of claim 38, wherein the catheter is intended tobe used to carry a guide wire or pacemaker lead in the channel.
 59. Thecatheter of claim 38, wherein the tubular member comprises a guide wireor pacemaker lead.
 60. A catheter and guide wire exchange systemcomprising a catheter configured to be inserted into a vessel within amammalian body, the catheter comprising: a tubular body having anexterior surface, a first end and a second end that define a lengthbetween the first end and the second end, a central lumen extendingalong the tubular body at least for a portion of the length of thetubular body, and a stiffening member positioned within at least aportion of the length of the tubular body; and at least one channelextending along the exterior surface of the tubular body at least for aportion of the length of the tubular body, the channel including a firstopening, a second opening, and the channel passing between the firstopening and the second opening, wherein the channel includes a slotopening into the channel such that a tubular member can be passedbetween the channel and the exterior surface of the tubular body,wherein the slot extends from the first opening to the second openingand includes a pair of edges, wherein the tubular body has acircumference that defines a non-circular shape.
 61. The catheter andguide wire exchange system of claim 60, wherein the stiffening member isone or more of a metal wire, a metal tube, a metal alloy tube, a coil,polyimide tube, or polyimide tube with a coil.
 62. The catheter andguide wire exchange system of claim 61, wherein the catheter shaft hasbeen formed by continually extruding thermoplastic over one or more ofthe metal tubing, metal wire, coil, metal alloy tube, a coil, polyimidetube, or polyimide tube with a coil, then cutting the extrudate intoindividual catheter lengths.
 63. The catheter and guide wire exchangesystem of claim 61, wherein the catheter shaft has been formed byextruding thermoplastic over discrete lengths of one or more of themetal tubing, metal wire, metal alloy tube, coil, polyimide tube, or apolyimide tube with a coil.
 64. The catheter and guide wire exchangesystem of claim 60, further comprising a balloon extending around thechannel and the tubular body proximal of the second end of the tubularbody.
 65. The catheter and guide wire exchange system of claim 64,wherein the balloon is a stent delivery balloon.